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AD5764BSUZ产品简介:
ICGOO电子元器件商城为您提供AD5764BSUZ由Analog设计生产,在icgoo商城现货销售,并且可以通过原厂、代理商等渠道进行代购。 AD5764BSUZ价格参考。AnalogAD5764BSUZ封装/规格:数据采集 - 数模转换器, 16 位 数模转换器 4 32-TQFP(7x7)。您可以下载AD5764BSUZ参考资料、Datasheet数据手册功能说明书,资料中有AD5764BSUZ 详细功能的应用电路图电压和使用方法及教程。
参数 | 数值 |
产品目录 | 集成电路 (IC)半导体 |
描述 | IC DAC 16BIT QUAD VOUT 32-TQFP数模转换器- DAC IC QUAD 16B +/-15V SERIAL INPT VOUT |
DevelopmentKit | EVAL-AD5764EBZ |
产品分类 | |
品牌 | Analog Devices Inc |
产品手册 | |
产品图片 | |
rohs | 符合RoHS无铅 / 符合限制有害物质指令(RoHS)规范要求 |
产品系列 | 数据转换器IC,数模转换器- DAC,Analog Devices AD5764BSUZ- |
数据手册 | |
产品型号 | AD5764BSUZ |
PCN设计/规格 | |
产品培训模块 | http://www.digikey.cn/PTM/IndividualPTM.page?site=cn&lang=zhs&ptm=19145http://www.digikey.cn/PTM/IndividualPTM.page?site=cn&lang=zhs&ptm=18614http://www.digikey.cn/PTM/IndividualPTM.page?site=cn&lang=zhs&ptm=26125http://www.digikey.cn/PTM/IndividualPTM.page?site=cn&lang=zhs&ptm=26140http://www.digikey.cn/PTM/IndividualPTM.page?site=cn&lang=zhs&ptm=26150http://www.digikey.cn/PTM/IndividualPTM.page?site=cn&lang=zhs&ptm=26147 |
产品目录页面 | |
产品种类 | 数模转换器- DAC |
位数 | 16 |
供应商器件封装 | 32-TQFP(7x7) |
分辨率 | 16 bit |
包装 | 托盘 |
商标 | Analog Devices |
安装类型 | 表面贴装 |
安装风格 | SMD/SMT |
封装 | Tray |
封装/外壳 | 32-TQFP |
封装/箱体 | TQFP-32 |
工作温度 | -40°C ~ 85°C |
工厂包装数量 | 250 |
建立时间 | 8µs |
接口类型 | SPI |
数据接口 | 串行 |
最大功率耗散 | 381 mW |
最大工作温度 | + 85 C |
最小工作温度 | - 40 C |
标准包装 | 1 |
电压参考 | Internal, External |
电压源 | 双 ± |
电源电压-最大 | 16.5 V |
电源电压-最小 | 11.4 V |
积分非线性 | +/- 2 LSB |
稳定时间 | 8 us |
系列 | AD5764 |
结构 | R-2R |
设计资源 | |
转换器数 | 4 |
转换器数量 | 4 |
输出数和类型 | 4 电压 |
输出类型 | Voltage |
配用 | /product-detail/zh/EVAL-AD5764EBZ/EVAL-AD5764EBZ-ND/1766887 |
采样比 | 1.26 MSPs |
采样率(每秒) | 1.26M |
Complete Quad, 16-Bit, High Accuracy, Serial Input, Bipolar Voltage Output DAC Data Sheet AD5764 FEATURES GENERAL DESCRIPTION Complete quad, 16-bit digital-to-analog The AD5764 is a quad, 16-bit, serial input, bipolar voltage converter (DAC) output DAC that operates from supply voltages of ±11.4 V to Programmable output range ±16.5 V. Nominal full-scale output range is ±10 V. The AD5764 ±10 V, ±10.2564 V, or ±10.5263 V provides integrated output amplifiers, reference buffers, and ±1 LSB maximum INL error, ±1 LSB maximum DNL error proprietary power-up/power-down control circuitry. The part Low noise: 60 nV/√Hz also features a digital I/O port that is programmed via the serial Settling time: 10 μs maximum interface. The part incorporates digital offset and gain adjust Integrated reference buffers registers per channel. Output control during power-up/brownout The AD5764 is a high performance converter that offers guar- Programmable short-circuit protection anteed monotonicity, integral nonlinearity (INL) of ±1 LSB, low Simultaneous updating via LDAC noise, and 10 μs settling time. During power-up (when the Asynchronous CLR to zero code supply voltages are changing), VOUTx is clamped to 0 V via a Digital offset and gain adjust low impedance path. Logic output control pins DSP-/microcontroller-compatible serial interface The AD5764 uses a serial interface that operates at clock rates of Temperature range: −40°C to +85°C up to 30 MHz and is compatible with DSP and microcontroller iCMOS process technology1 interface standards. Double buffering allows the simultaneous updating of all DACs. The input coding is programmable to APPLICATIONS either twos complement or offset binary formats. The asynchro- Industrial automation nous clear function clears the data register to either bipolar zero or Open-loop/closed-loop servo control zero scale depending on the coding used. The AD5764 is ideal Process control for both closed-loop servo control and open-loop control appli- Data acquisition systems cations. The AD5764 is available in a 32-lead TQFP, and offers Automatic test equipment guaranteed specifications over the −40°C to +85°C industrial Automotive test and measurement temperature range. See Figure 1 for the functional block diagram. High accuracy instrumentation Table 1. Related Devices Part No. Description AD5764R AD5764 with internal voltage reference AD5744R Complete quad, 14-bit, high accuracy, serial input, bipolar voltage output DAC with internal voltage reference 1 For analog systems designers within industrial/instrumentation equipment OEMs who need high performance ICs at higher voltage levels, iCMOS® is a technology platform that enables the development of analog ICs capable of 30 V and operating at ±15 V supplies, allowing dramatic reductions in power consumption and package size, and increased ac and dc performance. Rev. F Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 www.analog.com Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 ©2006–2011 Analog Devices, Inc. All rights reserved.
AD5764 Data Sheet TABLE OF CONTENTS Features..............................................................................................1 Function Register.......................................................................21 Applications.......................................................................................1 Data Register...............................................................................21 General Description.........................................................................1 Coarse Gain Register.................................................................21 Revision History...............................................................................2 Fine Gain Register......................................................................22 Functional Block Diagram..............................................................3 Offset Register............................................................................22 Specifications.....................................................................................4 Offset and Gain Adjustment Worked Example......................23 AC Performance Characteristics................................................5 Design Features...............................................................................24 Timing Characteristics................................................................6 Analog Output Control.............................................................24 Absolute Maximum Ratings............................................................9 Digital Offset and Gain Control...............................................24 ESD Caution..................................................................................9 Programmable Short-Circuit Protection................................24 Pin Configuration and Function Descriptions...........................10 Digital I/O Port...........................................................................24 Typical Performance Characteristics...........................................12 Local Ground Offset Adjust......................................................24 Terminology....................................................................................17 Applications Information..............................................................25 Theory of Operation......................................................................18 Typical Operating Circuit.........................................................25 DAC Architecture.......................................................................18 Layout Guidelines...........................................................................27 Reference Buffers........................................................................18 Galvanically Isolated Interface.................................................27 Serial Interface............................................................................18 Microprocessor Interfacing.......................................................27 Simultaneous Updating via LDAC...........................................19 Evaluation Board........................................................................27 Transfer Function.......................................................................20 Outline Dimensions.......................................................................28 Asynchronous Clear (CLR).......................................................20 Ordering Guide..........................................................................28 REVISION HISTORY 9/11—Rev. E to Rev. F Changes to Table 20.......................................................................26 Changed 30 MHz to 50 MHz Throughout....................................1 Deleted AD5764 to MC68HC11 Interface Section....................27 Changes to t, t, and t Parameters, Table 4..................................6 Deleted Figure 38; Renumbered Sequentially............................27 1 2 3 Deleted AD5764 to 8XC51 Interface Section, Figure 39, 7/11—Rev. D to Rev. E AD5764 to ADSP-2101 Interface Section, Figure 40, and Changed 30 MHz to 50 MHz Throughout....................................1 AD5764 to PIC16C6x/PIC16C7x Interface Section..................28 Changes to t, t, and t Parameters, Table 4..................................6 1 2 3 04/08—Rev. A to Rev. B 8/09—Rev. C to Rev. D Changes to Table Summary Statement, Specifications Section...4 Changes to Table 2 and Table 3 Endnotes.....................................6 Changes to Power Requirements Parameter, Table 2 and Changes to t Parameter and Endnotes, Table 4...........................7 6 Table Summary Statement................................................................5 1/09—Rev. B to Rev. C Changes to t Parameter, Table 4....................................................6 16 Changes to General Description Section......................................1 Changes to Table 6..........................................................................10 Changes to Figure 1..........................................................................3 Changed V /V to AV /AV in Typical Performance SS DD SS DD Changes to Table 2 Conditions.......................................................4 Characteristics Section..................................................................13 Changes to Table 3 Conditions.......................................................5 Changes to Table 16.......................................................................22 Changes to Table 4 Conditions.......................................................6 Changes to Table 18.......................................................................23 Changes to Figure 5..........................................................................8 Changes to Typical Operating Circuit Section...........................28 Changes to Table 5............................................................................9 Changes to AD5764 to ADSP-2101 Section...............................29 Changes to Table 6..........................................................................10 Changes to Ordering Guide..........................................................30 Changes to Figure 34......................................................................19 1/07—Rev. 0 to Rev. A Changes to Table 7 and Table 10...................................................20 Changes to Absolute Maximum Ratings.....................................10 Added Table 8; Renumbered Sequentially..................................20 Changes to Figure 25 and Figure 26.............................................16 Changes to Table 11 and Table 12................................................21 Changes to Digital Offset and Gain Control Section................24 3/06—Revision 0: Initial Version Rev. F | Page 2 of 28
Data Sheet AD5764 FUNCTIONAL BLOCK DIAGRAM PGND AVDD AVSS AVDD AVSS REFGND REFAB RSTOUT RSTIN VOLTAGE DVCC MONITOR AD5764 REFERENCE AND DGND BUFFERS CONTROL ISCC 16 16 G1 INPUT DATA SDIN INPUT REG A REG A DAC A VOUTA SHIFT G2 SCLK REGISTER AND GAIN REG A SYNC CONTROL OFFSET REG A AGNDA LOGIC SDO 16 G1 INPUT DATA REG B REG B DAC B VOUTB G2 GAIN REG B OFFSET REG B AGNDB D0 16 G1 INPUT DATA D1 REG C REG C DAC C VOUTC G2 GAIN REG C OFFSET REG C AGNDC BIN/2sCOMP 16 G1 INPUT DATA REG D REG D DAC D VOUTD G2 GAIN REG D CLR AGNDD OFFSET REG D REFERENCE BUFFERS LDAC REFCD 05303-001 Figure 1. Rev. F | Page 3 of 28
AD5764 Data Sheet SPECIFICATIONS AV = 11.4 V to 16.5 V, AV = −11.4 V to −16.5 V, AGNDx = DGND = REFGND = PGND = 0 V; REFAB = REFCD = 5 V; DD SS DV = 2.7 V to 5.25 V, R = 10 kΩ, C = 200 pF. Temperature range: −40°C to +85°C; typical at +25°C. Device functionality is CC LOAD L guaranteed to +105°C with degraded performance. All specifications T to T , unless otherwise noted. MIN MAX Table 2. Parameter A Grade B Grade C Grade Unit Test Conditions/Comments ACCURACY Outputs unloaded Resolution 16 16 16 Bits Relative Accuracy (INL) ±4 ±2 ±1 LSB max Differential Nonlinearity ±1 ±1 ±1 LSB max Guaranteed monotonic Bipolar Zero Error ±2 ±2 ±2 mV max At 25°C; error at other temperatures obtained using bipolar zero TC Bipolar Zero Temperature ±2 ±2 ±2 ppm FSR/°C max Coefficient (TC)1 Zero-Scale Error ±2 ±2 ±2 mV max At 25°C; error at other temperatures obtained using zero-scale TC Zero-Scale TC1 ±2 ±2 ±2 ppm FSR/°C max Gain Error ±0.02 ±0.02 ±0.02 % FSR max At 25°C; error at other temperatures obtained using gain TC Gain TC1 ±2 ±2 ±2 ppm FSR/°C max DC Crosstalk1 0.5 0.5 0.5 LSB max REFERENCE INPUT1 Reference Input Voltage 5 5 5 V nom ±1% for specified performance DC Input Impedance 1 1 1 MΩ min Typically 100 MΩ Input Current ±10 ±10 ±10 μA max Typically ±30 nA Reference Range 1 to 7 1 to 7 1 to 7 V min to V max OUTPUT CHARACTERISTICS1 Output Voltage Range2 ±10.5263 ±10.5263 ±10.5263 V min to V max AV /AV = ±11.4 V, V = 5 V DD SS REFIN ±14 ±14 ±14 V min to V max AV /AV = ±16.5 V, V = 7 V DD SS REFIN Output Voltage Drift vs. Time ±13 ±13 ±13 ppm FSR/ 500 hours typ ±15 ±15 ±15 ppm FSR/ 1000 hours typ Short-Circuit Current 10 10 10 mA typ R = 6 kΩ, see Figure 31 ISCC Load Current ±1 ±1 ±1 mA max For specified performance Capacitive Load Stability R = ∞ 200 200 200 pF max LOAD R = 10 kΩ 1000 1000 1000 pF max LOAD DC Output Impedance 0.3 0.3 0.3 Ω max DIGITAL INPUTS DV = 2.7 V to 5.25 V, JEDEC compliant CC Input High Voltage, V 2 2 2 V min IH Input Low Voltage, V 0.8 0.8 0.8 V max IL Input Current ±1 ±1 ±1 μA max Per pin Pin Capacitance 10 10 10 pF max Per pin Rev. F | Page 4 of 28
Data Sheet AD5764 Parameter A Grade B Grade C Grade Unit Test Conditions/Comments DIGITAL OUTPUTS (D0, D1, SDO)1 Output Low Voltage 0.4 0.4 0.4 V max DV = 5 V ± 5%, sinking 200 μA CC Output High Voltage DV − 1 DV − 1 DV − 1 V min DV = 5 V ± 5%, sourcing 200 μA CC CC CC CC Output Low Voltage 0.4 0.4 0.4 V max DV = 2.7 V to 3.6 V, sinking 200 μA CC Output High Voltage DV − 0.5 DV − 0.5 DV − 0.5 V min DV = 2.7 V to 3.6 V, sourcing 200 μA CC CC CC CC High Impedance Leakage Current ±1 ±1 ±1 μA max SDO only High Impedance Output 5 5 5 pF typ SDO only Capacitance POWER REQUIREMENTS AV /AV ±11.4 to ±11.4 to ±11.4 to V min to V max DD SS ±16.5 ±16.5 ±16.5 DV 2.7 to 5.25 2.7 to 5.25 2.7 to 5.25 V min to V max CC Power Supply Sensitivity1 ∆V /∆ΑV −85 −85 −85 dB typ OUT DD AI 3.5 3.5 3.5 mA/channel max Outputs unloaded DD AI 2.75 2.75 2.75 mA/channel max Outputs unloaded SS DI 1.2 1.2 1.2 mA max V = DV , V = DGND, 750 μA typical CC IH CC IL Power Dissipation 275 275 275 mW typ ±12 V operation output unloaded 1 Guaranteed by design and characterization; not production tested. 2 Output amplifier headroom requirement is 1.4 V minimum. AC PERFORMANCE CHARACTERISTICS AV = 11.4 V to 16.5 V, AV = −11.4 V to −16.5 V, AGNDx = DGND = REFGND = PGND = 0 V; REFAB = REFCD = 5 V; DD SS DV = 2.7 V to 5.25 V, R = 10 kΩ, C = 200 pF. All specifications T to T , unless otherwise noted. CC LOAD L MIN MAX Table 3. Parameter A Grade B Grade C Grade Unit Test Conditions/Comments DYNAMIC PERFORMANCE1 Output Voltage Settling Time 8 8 8 μs typ Full-scale step to ±1 LSB 10 10 10 μs max 2 2 2 μs typ 512 LSB step settling Slew Rate 5 5 5 V/μs typ Digital-to-Analog Glitch Energy 8 8 8 nV-sec typ Glitch Impulse Peak Amplitude 25 25 25 mV max Channel-to-Channel Isolation 80 80 80 dB typ DAC-to-DAC Crosstalk 8 8 8 nV-sec typ Digital Crosstalk 2 2 2 nV-sec typ Digital Feedthrough 2 2 2 nV-sec typ Effect of input bus activity on DAC outputs Output Noise (0.1 Hz to 10 Hz) 0.1 0.1 0.1 LSB p-p typ Output Noise (0.1 Hz to 100 kHz) 45 45 45 μV rms max 1/f Corner Frequency 1 1 1 kHz typ Output Noise Spectral Density 60 60 60 nV/√Hz typ Measured at 10 kHz Complete System Output Noise Spectral 80 80 80 nV/√Hz typ Measured at 10 kHz Density2 1 Guaranteed by design and characterization; not production tested. 2 Includes noise contributions from integrated reference buffers, 16-bit DAC, and output amplifier. Rev. F | Page 5 of 28
AD5764 Data Sheet TIMING CHARACTERISTICS AV = 11.4 V to 16.5 V, AV = −11.4 V to −16.5 V, AGNDx = DGND = REFGND = PGND = 0 V; REFAB = REFCD = 5 V; DD SS DV = 2.7 V to 5.25 V, R = 10 kΩ, C = 200 pF. All specifications T to T , unless otherwise noted. CC LOAD L MIN MAX Table 4. Parameter1, 2, 3 Limit at T , T Unit Description MIN MAX t 33 ns min SCLK cycle time 1 t 13 ns min SCLK high time 2 t 13 ns min SCLK low time 3 t 13 ns min SYNC falling edge to SCLK falling edge setup time 4 t 4 13 ns min 24th SCLK falling edge to SYNC rising edge 5 t 90 ns min Minimum SYNC high time 6 t 2 ns min Data setup time 7 t 5 ns min Data hold time 8 t 1.7 μs min SYNC rising edge to LDAC falling edge (all DACs updated) 9 480 ns min SYNC rising edge to LDAC falling edge (single DAC updated) t 10 ns min LDAC pulse width low 10 t 500 ns max LDAC falling edge to DAC output response time 11 t 10 μs max DAC output settling time 12 t 10 ns min CLR pulse width low 13 t 2 μs max CLR pulse activation time 14 t 5, 6 25 ns max SCLK rising edge to SDO valid 15 t 13 ns min SYNC rising edge to SCLK falling edge 16 t 2 μs max SYNC rising edge to DAC output response time (LDAC = 0) 17 t 170 ns min LDAC falling edge to SYNC rising edge 18 1 Guaranteed by design and characterization; not production tested. 2 All input signals are specified with tR = tF = 5 ns (10% to 90% of DVCC) and timed from a voltage level of 1.2 V. 3 See Figure 2, Figure 3, and Figure 4. 4 Standalone mode only. 5 Measured with the load circuit of Figure 5. 6 Daisy-chain mode only. Rev. F | Page 6 of 28
Data Sheet AD5764 Timing Diagrams t 1 SCLK 1 2 24 t6 t3 t2 t4 t5 SYNC t 8 t 7 SDIN DB23 DB0 t10 t t10 9 LDAC t18 t12 t 11 VOUTx LDAC = 0 t 12 t 17 VOUTx t CLR 13 t 14 VOUTx 05303-002 Figure 2. Serial Interface Timing Diagram t 1 SCLK 24 48 t6 t3 t2 t5 t t 16 4 SYNC t 8 t 7 SDIN DB23 DB0 DB23 DB0 INPUT WORD FOR DAC N INPUT WORD FOR DAC N–1 t 15 SDO DB23 DB0 UNDEFINED INPUT WORD FOR DAC N t9 t 10 LDAC 05303-003 Figure 3. Daisy-Chain Timing Diagram Rev. F | Page 7 of 28
AD5764 Data Sheet SCLK 24 48 SYNC SDIN DB23 DB0 DB23 DB0 INPUT WORD SPECIFIES NOP CONDITION REGISTER TO BE READ SDO DB23 DB0 UNDEFINED SELECCTLEOD CRKEEGDIS OTUETR DATA 05303-004 Figure 4. Readback Timing Diagram 200µA IOL TO SDO VOH (MIN) OR PIN CL VOL (MAX) 50pF 200µA IOH 05303-005 Figure 5. Load Circuit for SDO Timing Diagram Rev. F | Page 8 of 28
Data Sheet AD5764 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. Transient currents of up to Stresses above those listed under Absolute Maximum Ratings A 100 mA do not cause SCR latch-up. may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any Table 5. other conditions above those listed in the operational sections Parameter Rating of this specification is not implied. Exposure to absolute AVDD to AGNDx, DGND −0.3 V to +17 V maximum rating conditions for extended periods may affect AVSS to AGNDx, DGND +0.3 V to −17 V device reliability. DV to DGND −0.3 V to +7 V CC Digital Inputs to DGND −0.3 V to DV + 0.3 V or 7 V CC (whichever is less) ESD CAUTION Digital Outputs to DGND −0.3 V to DV + 0.3 V CC REFAB, REFCD to AGNDx, PGND −0.3 V to AV + 0.3 V DD VOUTA, VOUTB, VOUTC, VOUTD to AV to AV SS DD AGNDx AGNDx to DGND −0.3 V to +0.3 V Operating Temperature Range Industrial −40°C to +85°C Storage Temperature Range −65°C to +150°C Junction Temperature (T max) 150°C J 32-Lead TQFP θ Thermal Impedance 65°C/W JA θ Thermal Impedance 12°C/W JC Lead Temperature JEDEC industry standard Soldering J-STD-020 Rev. F | Page 9 of 28
AD5764 Data Sheet PIN CONFIGURATION AND FUNCTION DESCRIPTIONS P M BIN/2sCO AVDDAVSS NC REFGND NC REFCD REFAB 32 31 30 29 28 27 26 25 SYNC 1 24 AGNDA SCLK 2 PIN 1 23 VOUTA SDIN 3 AD5764 22 VOUTB SDO 4 21 AGNDB TOP VIEW CLR 5 (Not to Scale) 20 AGNDC LDAC 6 19 VOUTC D0 7 18 VOUTD D1 8 17 AGNDD 9 10 11 12 13 14 15 16 T N D C D D S C RSTOU RSTINCDGN = NDVCO CAVDONPGNNEAVCSTISC 05303-006 Figure 6. Pin Configuration Table 6. Pin Function Descriptions Pin No. Mnemonic Description 1 SYNC Active Low Input. This is the frame synchronization signal for the serial interface. While SYNC is low, data is transferred in on the falling edge of SCLK. 2 SCLK Serial Clock Input. Data is clocked into the input shift register on the falling edge of SCLK. This operates at clock speeds up to 30 MHz. 3 SDIN Serial Data Input. Data must be valid on the falling edge of SCLK. 4 SDO Serial Data Output. Used to clock data from the serial register in daisy-chain or readback mode. 5 CLR Negative Edge Triggered Input. Asserting this pin sets the data register to 0x0000. There is an internal pull-up device on this logic input. Therefore, this pin can be left floating and defaults to a Logic 1 condition. 6 LDAC Load DAC. Logic input. This is used to update the data register and consequently the analog outputs. When tied permanently low, the addressed data register is updated on the rising edge of SYNC. If LDAC is held high during the write cycle, the DAC input shift register is updated but the output update is held off until the falling edge of LDAC. In this mode, all analog outputs can be updated simultaneously on the falling edge of LDAC. The LDAC pin must not be left unconnected. 7, 8 D0, D1 Digital I/O Port. The user can set up these pins as inputs or outputs that are configurable and readable over the serial interface. When configured as inputs, these pins have weak internal pull-ups to DV . CC When programmed as outputs, D0 and D1 are referenced by DV and DGND. CC 9 RSTOUT Reset Logic Output. This is the output from the on-chip voltage monitor used in the reset circuit. If desired, it can be used to control other system components. 10 RSTIN Reset Logic Input. This input allows external access to the internal reset logic. Applying a Logic 0 to this input clamps the DAC outputs to 0 V. In normal operation, RSTIN should be tied to Logic 1. Register values remain unchanged. 11 DGND Digital Ground. 12 DV Digital Supply. Voltage ranges from 2.7 V to 5.25 V. CC 13, 31 AV Positive Analog Supply. Voltage ranges from 11.4 V to 16.5 V. DD 14 PGND Ground Reference Point for Analog Circuitry. 15, 30 AV Negative Analog Supply. Voltage ranges from −11.4 V to −16.5 V. SS 16 ISCC Resistor Connection for Pin Programmable Short-Circuit Current. This pin is used in association with an optional external resistor to AGND to program the short-circuit current of the output amplifiers. Refer to the Design Features section for further details. 17 AGNDD Ground Reference Pin for DAC D Output Amplifier. 18 VOUTD Analog Output Voltage of DAC D. This pin is a buffered output with a nominal full-scale output range of ±10 V. The output amplifier is capable of directly driving a 10 kΩ, 200 pF load. 19 VOUTC Analog Output Voltage of DAC C. This pin is a buffered output with a nominal full-scale output range of ±10 V. The output amplifier is capable of directly driving a 10 kΩ, 200 pF load. 20 AGNDC Ground Reference Pin for DAC C Output Amplifier. Rev. F | Page 10 of 28
Data Sheet AD5764 Pin No. Mnemonic Description 21 AGNDB Ground Reference Pin for DAC B Output Amplifier. 22 VOUTB Analog Output Voltage of DAC B. Buffered output with a nominal full-scale output range of ±10 V. The output amplifier is capable of directly driving a 10 kΩ, 200 pF load. 23 VOUTA Analog Output Voltage of DAC A. Buffered output with a nominal full-scale output range of ±10 V. The output amplifier is capable of directly driving a 10 kΩ, 200 pF load. 24 AGNDA Ground Reference Pin for DAC A Output Amplifier. 25 REFAB External Reference Voltage Input for Channel A and Channel B. Reference input range is 1 V to 7 V; programs the full-scale output voltage. V = 5 V for specified performance. REFIN 26 REFCD External Reference Voltage Input for Channel C and Channel D. Reference input range is 1 V to 7 V; programs the full-scale output voltage. V = 5 V for specified performance. REFIN 27, 29 NC No Connect. 28 REFGND Reference Ground Return for the Reference Generator and Buffers. 32 BIN/2sCOMP Determines the DAC Coding. This pin should be hardwired to either DV or DGND. When hardwired to CC DV , input coding is offset binary. When hardwired to DGND, input coding is twos complement CC (see Table 7 and Table 8). Rev. F | Page 11 of 28
AD5764 Data Sheet TYPICAL PERFORMANCE CHARACTERISTICS 1.0 1.0 TA = 25°C TA = 25°C 0.8 AVDD/AVSS = ±15V 0.8 AVDD/AVSS = ±12V VREFIN = 5V VREFIN = 5V 0.6 0.6 0.4 0.4 B) B) R (LS 0.2 R (LS 0.2 O 0 O 0 R R R R NL E –0.2 NL E –0.2 I –0.4 D –0.4 –0.6 –0.6 ––10..08 05303-007 ––10..08 05303-012 0 10000 20000 30000 40000 50000 60000 0 10000 20000 30000 40000 50000 60000 DAC CODE DAC CODE Figure 7. Integral Nonlinearity Error vs. Code, Figure 10. Differential Nonlinearity Error vs. Code, AVDD/AVSS = ±15 V AVDD/AVSS = ±12 V 1.0 0.5 TA = 25°C TA = 25°C 0.8 AVDD/AVSS = ±12V AVDD/AVSS = ±15V VREFIN = 5V 0.4 VREFIN = 5V 0.6 0.4 0.3 B) B) R (LS 0.2 R (LS 0.2 O 0 O R R L ER –0.2 L ER 0.1 N N I –0.4 I 0 –0.6 –0.1 ––10..08 05303-008 –0.2 05303-015 0 10000 20000 30000 40000 50000 60000 –40 –20 0 20 40 60 80 100 DAC CODE TEMPERATURE (°C) Figure 8. Integral Nonlinearity Error vs. Code, Figure 11. Integral Nonlinearity Error vs. Temperature, AVDD/AVSS = ±12 V AVDD/AVSS = ±15 V 1.0 0.5 00..68 TVAARV ED=FD I2N/A5 =°VC S5SV = ±15V 0.4 TVAARV ED=FD I2N/A5 °=VC S5SV = ±12V 0.4 B) B) 0.3 R (LS 0.2 R (LS O 0 O 0.2 R R R R DNL E ––00..42 INL E 0.1 –0.6 0 ––10..08 05303-011 –0.1 05303-016 0 10000 20000 30000 40000 50000 60000 –40 –20 0 20 40 60 80 100 DAC CODE TEMPERATURE (°C) Figure 9. Differential Nonlinearity Error vs. Code, Figure 12. Integral Nonlinearity Error vs. Temperature, AVDD/AVSS = ±15 V AVDD/AVSS = ±12 V Rev. F | Page 12 of 28
Data Sheet AD5764 0.15 0.15 TA = 25°C VREFIN = 5V 0.10 0.10 0.05 0.05 B) B) S 0 S 0 L L R ( R ( O–0.05 O–0.05 R R R R E E L –0.10 L –0.10 N N D D –0.15 –0.15 ––00..2250 TVAARV ED=FD I2N/A5 °=VC S5SV = ±15V 05303-019 ––00..2250 05303-025 –40 –20 0 20 40 60 80 100 11.4 12.4 13.4 14.4 15.4 16.4 TEMPERATURE (°C) SUPPLY VOLTAGE (V) Figure 13. Differential Nonlinearity Error vs. Temperature, Figure 16. Differential Nonlinearity Error vs. Supply Voltage AVDD/AVSS = ±15 V 0.15 0.8 TA = 25°C 0.10 0.6 AVDD/AVSS = ±16.5V 0.4 0.05 SB) 0 SB) 0.2 R (L R (L 0 O–0.05 O R R R R –0.2 E E DNL –0.10 INL –0.4 –0.15 –0.6 ––00..2250 TVAARV ED=FD I2N/A5 °=VC S5SV = ±12V 05303-020 ––10..08 05303-027 –40 –20 0 20 40 60 80 100 1 2 3 4 5 6 7 TEMPERATURE (°C) REFERENCE VOLTAGE (V) Figure 14. Differential Nonlinearity Error vs. Temperature, Figure 17. Integral Nonlinearity Error vs. Reference Voltage, AVDD/AVSS = ±12 V AVDD/AVSS = ±16.5 V 0.5 0.4 TA = 25°C TA = 25°C 0.4 VREFIN = 5V 0.3 AVDD/AVSS = ±16.5V 0.2 0.3 INL ERROR (LSB) 00..21 DNL ERROR (LSB) –00..110 0 –0.2 ––00..21 05303-023 ––00..43 05303-031 11.4 12.4 13.4 14.4 15.4 16.4 1 2 3 4 5 6 7 SUPPLY VOLTAGE (V) REFERENCE VOLTAGE (V) Figure 15. Integral Nonlinearity Error vs. Supply Voltage Figure 18. Differential Nonlinearity Error vs. Reference Voltage, AVDD/AVSS = ±16.5 V Rev. F | Page 13 of 28
AD5764 Data Sheet 0.6 0.8 0.4 TAAV D=D 2/A5°VCSS = ±16.5V VREFIN = 5V AVDD/AVSS = ±15V 0.2 0.6 V) 0 m R ( 0.4 –0.2 RO AVDD/AVSS = ±12V UE (mV) ––00..64 ERO ER 0.2 T Z –0.8 LAR 0 –1.0 PO BI –1.2 –0.2 ––11..64 05303-035 –0.4 05303-039 1 2 3 4 5 6 7 –40 –20 0 20 40 60 80 100 REFERENCE VOLTAGE (V) TEMPERATURE (°C) Figure 19. Total Unadjusted Error vs. Reference Voltage, Figure 22. Bipolar Zero Error vs. Temperature AVDD/AVSS = ±16.5 V 14 1.4 TA = 25°C VREFIN = 5V VREFIN = 5V 1.2 13 1.0 |IDD| AVDD/AVSS = ±12V 12 V) m 0.8 mA) OR ( I/I (DDSS 11 AIN ERR 00..64 10 G AVDD/AVSS = ±15V |ISS| 0.2 9 8 05303-037 –0.20 05303-040 11.4 12.4 13.4 14.4 15.4 16.4 –40 –20 0 20 40 60 80 100 AVDD/AVSS (V) TEMPERATURE (°C) Figure 20. IDD/ISS vs. AVDD/AVSS Figure 23. Gain Error vs. Temperature 0.25 0.0014 VREFIN = 5V AVDD/AVSS = ±15V TA = 25°C 0.20 0.0013 0.15 5V mV) 0.10 AVDD/AVSS = ±12V 0.0012 R ( 0.0011 RO 0.05 A) R m E E 0 (C0.0010 CAL–0.05 DIC0.0009 S O- R–0.10 E 0.0008 Z –0.15 3V ––00..2250 05303-038 00..00000076 05303-041 –40 –20 0 20 40 60 80 100 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 TEMPERATURE (°C) VLOGIC Figure 21. Zero-Scale Error vs. Temperature Figure 24. DICC vs. Logic Input Voltage Rev. F | Page 14 of 28
Data Sheet AD5764 7000 TA = 25°C AVDD/AVSS = ±15V VREFIN = 5V TA = 25°C 6000 RISCC = 6kΩ AVDD/AVSS = ±15V VREFIN = 5V V) µ 5000 A ( AVDD/AVSS = ±12V T EL 4000 D E G A 3000 T L O V 2000 T U P T 1000 U O –10000 05303-042 1 1µs/DIV 05303-044 –10 –5 0 5 10 CH1 3.00V M1.00µs CH1 –120mV SOURCE/SINK CURRENT (mA) Figure 25. Source and Sink Capability of Output Amplifier with Figure 27. Full-Scale Settling Time Positive Full Scale Loaded 10000 –4 TA = 25°C 9000 VREFIN = 5V –6 8000 RISCC = 6kΩ –8 V) 15V SUPPLIES A (µ 7000 –10 T EL 6000 –12 E D 5000 12V SUPPLIES mV) –14 OLTAG 4000 V (OUT –16 T V 3000 –18 U TP 2000 –20 AVDD/AVSS = ±12V OU 1000 –22 TVAR E=F I2N5 °=C 5V –10000 05303-043 ––2246 05x0800n0s0/D TIVO 0x7FFF 05303-047 –12 –7 –2 3 8 –2.0–1.5–1.0–0.5 0 0.51.01.52.02.53.03.54.04.55.05.56.0 SOURCE/SINK CURRENT (mA) TIME (µs) Figure 26. Source and Sink Capability of Output Amplifier with Figure 28. Major Code Transition Glitch Energy, AVDD/AVSS = ±12 V Negative Full Scale Loaded Rev. F | Page 15 of 28
AD5764 Data Sheet 10 MVARVIDEDFSDICN/A A=VL S0ESV L=O ±A1D5VED 9 ATVARV ED=FD I2N/A5 °=VC S5SV = ±15V A) 8 m T ( 7 N E RR 6 U 4 T C 5 UI RC 4 CI T- 3 R O H 2 S 50µV/DIV 05303-048 10 05303-050 CH4 50.0µV M1.00s CH4 26µV 0 20 40 60 80 100 120 RISCC (kΩ) Figure 29. Peak-to-Peak Noise (100 kHz Bandwidth) Figure 31. Short-Circuit Current vs. RISCC T AVDD/AVSS = ±12V 1 VREFIN = 5V 2 TA = 25°C RAMP TIME = 100µs LOAD = 200pF||10kΩ 3 05303-055 CH1 10.0VBW CH2 10.0V M100µs A CH1 7.80mV CH3 10.0mVBW T 29.60% Figure 30. VOUT vs. AVDD/AVSS on Power-Up Rev. F | Page 16 of 28
Data Sheet AD5764 TERMINOLOGY Total Unadjusted Error Relative Accuracy or Integral Nonlinearity (INL) Total unadjusted error (TUE) is a measure of the output error For the DAC, relative accuracy or integral nonlinearity (INL) is considering all the various errors. A plot of total unadjusted a measure of the maximum deviation, in LSBs, from a straight error vs. reference voltage can be seen in Figure 19. line passing through the endpoints of the DAC transfer function. A typical INL vs. code plot can be seen in Figure 7. Zero-Scale Error Temperature Coefficient (TC) Zero-scale error TC is a measure of the change in zero-scale Differential Nonlinearity (DNL) error with a change in temperature. Zero-scale error TC is Differential nonlinearity is the difference between the measured expressed in ppm FSR/°C. change and the ideal 1 LSB change between any two adjacent codes. A specified differential nonlinearity of ±1 LSB maximum Gain Error Temperature Coefficient (TC) ensures monotonicity. This DAC is guaranteed monotonic. A Gain error TC is a measure of the change in gain error with typical DNL vs. code plot can be seen in Figure 9. changes in temperature. Gain error TC is expressed in ppm FSR/°C. Monotonicity A DAC is monotonic if the output either increases or remains Digital-to-Analog Glitch Energy constant for increasing digital input code. The AD5764 is Digital-to-analog glitch impulse is the impulse injected into the monotonic over its full operating temperature range. analog output when the input code in the data register changes state. It is normally specified as the area of the glitch in nV-sec, Bipolar Zero Error and is measured when the digital input code is changed by 1 LSB at Bipolar zero error is the deviation of the analog output from the the major carry transition (0x7FFF to 0x8000); see Figure 28. ideal half-scale output of 0 V when the data register is loaded with 0x8000 (offset binary coding) or 0x0000 (twos complement Digital Feedthrough coding). A plot of bipolar zero error vs. temperature can be seen Digital feedthrough is a measure of the impulse injected into in Figure 22. the analog output of the DAC from the digital inputs of the DAC but is measured when the DAC output is not updated. It is speci- Bipolar Zero Temperature Coefficient (TC) fied in nV-sec and measured with a full-scale code change on Bipolar zero TC is the measure of the change in the bipolar zero the data bus, that is, from all 0s to all 1s, and vice versa. error with a change in temperature. It is expressed in ppm FSR/°C. Power Supply Sensitivity Full-Scale Error Power supply sensitivity indicates how the output of the DAC is Full-scale error is a measure of the output error when full-scale affected by changes in the power supply voltage. code is loaded to the data register. Ideally, the output voltage should be 2 × V − 1 LSB. Full-scale error is expressed in DC Crosstalk REF percentage of full-scale range. DC crosstalk is the dc change in the output level of one DAC in response to a change in the output of another DAC. It is measured Negative Full-Scale Error/Zero-Scale Error with a full-scale output change on one DAC while monitoring Negative full-scale error is the error in the DAC output voltage another DAC, and is expressed in LSBs. when 0x0000 (offset binary coding) or 0x8000 (twos complement coding) is loaded to the data register. Ideally, the output voltage DAC-to-DAC Crosstalk should be −2 × V . A plot of zero-scale error vs. temperature DAC-to-DAC crosstalk is the glitch impulse transferred to the REF can be seen in Figure 21. output of one DAC due to a digital code change and subsequent output change of another DAC. This includes both digital and Output Voltage Settling Time analog crosstalk. It is measured by loading one of the DACs with Output voltage settling time is the amount of time it takes for the a full-scale code change (all 0s to all 1s and vice versa) with LDAC output to settle to a specified level for a full-scale input change. low and monitoring the output of another DAC. The energy of Slew Rate the glitch is expressed in nV-sec. The slew rate of a device is a limitation in the rate of change of Channel-to-Channel Isolation the output voltage. The output slewing speed of a voltage-output Channel-to-channel isolation is the ratio of the amplitude of the DAC is usually limited by the slew rate of the amplifier used at signal at the output of one DAC to a sine wave on the reference its output. Slew rate is measured from 10% to 90% of the output input of another DAC. It is measured in dB. signal and is given in V/μs. Digital Crosstalk Gain Error Gain error is a measure of the span error of the DAC. It is the Digital crosstalk is a measure of the impulse injected into the deviation in slope of the DAC transfer characteristic from the analog output of one DAC from the digital inputs of another DAC, ideal, expressed as a percentage of the full-scale range. A plot of but is measured when the DAC output is not updated. It is specified gain error vs. temperature can be seen in Figure 23. in nV-sec and measured with a full-scale code change on the data bus, that is, from all 0s to all 1s, and vice versa. Rev. F | Page 17 of 28
AD5764 Data Sheet THEORY OF OPERATION The AD5764 is a quad, 16-bit, serial input, bipolar voltage output SERIAL INTERFACE DAC and operates from supply voltages of ±11.4 V to ±16.5 V and The AD5764 is controlled over a versatile 3-wire serial interface has a buffered output voltage of up to ±10.5263 V. Data is written to that operates at clock rates of up to 30 MHz and is compatible the AD5764 in a 24-bit word format, via a 3-wire serial interface. with SPI, QSPI™, MICROWIRE™, and DSP standards. The device also offers an SDO pin that is available for daisy- Input Shift Register chaining or readback. The input shift register is 24 bits wide. Data is loaded into the The AD5764 incorporates a power-on reset circuit, which ensures device MSB first as a 24-bit word under the control of a serial that the data register powers up loaded with 0x0000. The AD5764 clock input, SCLK. The input shift register consists of a read/ features a digital I/O port that can be programmed via the serial write bit, three register select bits, three DAC address bits, and interface, on-chip reference buffers and per channel digital gain, 16 data bits, as shown in Table 9. The timing diagram for this and offset registers. operation is shown in Figure 2. DAC ARCHITECTURE Upon power-up, the data register is loaded with zero code The DAC architecture of the AD5764 consists of a 16-bit, (0x0000), and the outputs are clamped to 0 V via a low imped- current mode, segmented R-2R DAC. The simplified circuit ance path. The outputs can be updated with the zero code value diagram for the DAC section is shown in Figure 32. at this time by asserting either LDAC or CLR. The corresponding The four MSBs of the 16-bit data word are decoded to drive output voltage depends on the state of the BIN/2sCOMP pin. If 15 switches, E1 to E15. Each of these switches connects one of the BIN/2sCOMP pin is tied to DGND, the data coding is twos the 15 matched resistors to either AGNDx or IOUT. The remain- complement, and the outputs update to 0 V. If the BIN/2sCOMP ing 12 bits of the data-word drive Switch S0 to Switch S11 of pin is tied to DV , the data coding is offset binary, and the CC the 12-bit R-2R ladder network. outputs update to negative full scale. To power up the outputs VREF R R R with zero code loaded to the outputs, hold the CLR pin low during power-up. 2R 2R 2R 2R 2R 2R 2R Standalone Operation R/8 The serial interface works with both a continuous and noncon- E15 E14 E1 S11 S10 S0 tinuous serial clock. A continuous SCLK source can only be IOUT used if SYNC is held low for the correct number of clock cycles. In gated clock mode, a burst clock containing the exact number VOUTx AGNDx 41 M5 SEBQsU DAELC SOEDGEMDE INNTTSO 12-BIT, R-2R LADDER 05303-060 othf ec lfoincakl ccyloclceks tmo ulasttc bhe t uhsee dda atan.d T ShYeN fiCrs tm faulslti nbge etdakgeen o fh SigYhN aCft er Figure 32. DAC Ladder Structure starts the write cycle. Exactly 24 falling clock edges must be REFERENCE BUFFERS applied to SCLK before SYNC is brought high again. If SYNC is brought high before the 24th falling SCLK edge, the data written The AD5764 operates with an external reference. The reference is invalid. If more than 24 falling SCLK edges are applied before inputs (REFAB and REFCD) have an input range up to 7 V. This SYNC is brought high, the input data is also invalid. The input input voltage is used to provide a buffered positive and negative shift register addressed is updated on the rising edge of SYNC. reference for the DAC cores. The positive reference is given by For another serial transfer to take place, SYNC must be brought +V = 2 × V REF REF low again. After the end of the serial data transfer, data is The negative reference to the DAC cores is given by automatically transferred from the input shift register to the −V = −2 × V addressed register. REF REF These positive and negative reference voltages (along with the When the data has been transferred into the chosen register of gain register values) define the output ranges of the DACs. the addressed DAC, the data register and outputs can be updated by taking LDAC low. Rev. F | Page 18 of 28
Data Sheet AD5764 Daisy-Chain Operation disable bit; this bit is cleared by default. Readback mode is invoked by setting the R/W bit = 1 in the serial input shift register write. 68HC111 AD57641 With R/W = 1, Bit A2 to Bit A0, in association with Bit REG2, MOSI SDIN Bit REG1, and Bit REG0, select the register to be read. The SCK SCLK remaining data bits in the write sequence are don’t cares. During PC7 SYNC the next SPI write, the data appearing on the SDO output PC6 LDAC contain the data from the previously addressed register. For a MISO SDO read of a single register, the NOP command can be used in clocking out the data from the selected register on SDO. The SDIN readback diagram in Figure 4 shows the readback sequence. For AD57641 example, to read back the fine gain register of Channel A on the AD5764, implement the following: SCLK 1. Write 0xA0XXXX to the AD5764 input shift register. This SYNC configures the AD5764 for read mode with the fine gain LDAC register of Channel A selected. Note that all the data bits, SDO DB15 to DB0, are don’t cares. 2. Follow this with a second write, an NOP condition, SDIN 0x00XXXX. During this write, the data from the fine gain AD57641 register is clocked out on the SDO line, that is, data clocked SCLK out contain the data from the fine gain register in Bit DB5 SYNC to Bit DB0. LDAC SIMULTANEOUS UPDATING VIA LDAC SDO 1ADDITIONAL PINS OMITTED FOR CLARITY 05303-061 dDaetpa ehnadsi nbege onn t rthane ssfteartruesd o ifn btoo tthh eS YinNpCut arnegdi sLtDerA oCf ,t hane dD aAftCesr, Figure 33. Daisy-Chaining the AD5764 there are two ways in which the data register and DAC outputs can be updated. For systems that contain several devices, the SDO pin can be used to daisy-chain several devices together. This daisy-chain Individual DAC Updating mode can be useful in system diagnostics and in reducing the In this mode, LDAC is held low while data is being clocked into number of serial interface lines. The first falling edge of SYNC the input shift register. The addressed DAC output is updated starts the write cycle. The SCLK is continuously applied to the on the rising edge of SYNC. input shift register when SYNC is low. If more than 24 clock Simultaneous Updating of All DACs pulses are applied, the data ripples out of the input shift register and appears on the SDO line. This data is clocked out on the In this mode, LDAC is held high while data is being clocked rising edge of SCLK and is valid on the falling edge. By connect- into the input shift register. All DAC outputs are updated by ing the SDO of the first device to the SDIN input of the next device taking LDAC low any time after SYNC has been taken high. in the chain, a multidevice interface is constructed. Each device in The update now occurs on the falling edge of LDAC. the system requires 24 clock pulses. Therefore, the total number of OUTPUT clock cycles must equal 24N, where N is the total number of I/V AMPLIFIER AD5764 devices in the chain. When the serial transfer to all VREFIN 1D6-ABCIT VOUTx devices is complete, SYNC is taken high. This latches the input data in each device in the daisy chain and prevents any further DATA data from being clocked into the input shift register. The serial LDAC REGISTER clock can be a continuous or a gated clock. A continuous SCLK source can only be used if SYNC is held low INPUT REGISTER for the correct number of clock cycles. In gated clock mode, a burst clock containing the exact number of clock cycles must be used, aRneda SdYbNaCck m Oupste brea ttaiokenn high after the final clock to latch the data. SSSYCDNLICNK INTLEORGFIACCE SDO 05303-062 Figure 34. Simplified Serial Interface of Input Loading Circuitry Before a readback operation is initiated, the SDO pin must be for One DAC Channel enabled by writing to the function register and clearing the SDO Rev. F | Page 19 of 28
AD5764 Data Sheet TRANSFER FUNCTION The output voltage expression for the AD5764 is given by Table 7 and Table 8 show the ideal input code to output voltage ⎡ D ⎤ relationship for the AD5764 for both offset binary and twos VOUT =−2×VREFIN +4×VREFIN⎢⎣65,536⎥⎦ complement data coding, respectively. where: Table 7. Ideal Output Voltage to Input Code Relationship— D is the decimal equivalent of the code loaded to the DAC. Offset Binary Data Coding V is the reference voltage applied at the REFAB/REFCD pins. REFIN Digital Input Analog Output MSB LSB VOUTx ASYNCHRONOUS CLEAR (CLR) 1111 1111 1111 1111 +2 V × (32,767/32,768) REF CLR is a negative edge triggered clear that allows the outputs to 1000 0000 0000 0001 +2 V × (1/32,768) REF be cleared to either 0 V (twos complement coding) or negative 1000 0000 0000 0000 0 V full scale (offset binary coding). It is necessary to maintain CLR 0111 1111 1111 1111 −2 V × (1/32,768) REF low for a minimum amount of time (see Figure 2) for the operation 0000 0000 0000 0000 −2 V × (32,767/32,768) REF to complete. When the CLR signal is returned high, the output remains at the cleared value until a new value is programmed. If Table 8. Ideal Output Voltage to Input Code Relationship— at power-on, CLR is at 0 V, then all DAC outputs are updated Twos Complement Data Coding with the clear value. A clear can also be initiated through software Digital Input Analog Output by writing Command 0x04XXXX to the AD5764. MSB LSB VOUTx 0111 1111 1111 1111 +2 V × (32,767/32,768) REF 0000 0000 0000 0001 +2 V × (1/32,768) REF 0000 0000 0000 0000 0 V 1111 1111 1111 1111 −2 V × (1/32,768) REF 1000 0000 0000 0000 −2 V × (32,767/32,768) REF Table 9. Input Shift Register Bit Map MSB LSB DB23 DB22 DB21 DB20 DB19 DB18 DB17 DB16 DB15:DB0 R/W 0 REG2 REG1 REG0 A2 A1 A0 Data Table 10. Input Shift Register Bit Functions Bit Description R/W Indicates a read from or a write to the addressed register. REG2, REG1, REG0 Used in association with the address bits to determine if a read or write operation is to the data register, offset register, coarse gain register, fine gain register, or function register. REG2 REG1 REG0 Function 0 0 0 Function register 0 1 0 Data register 0 1 1 Coarse gain register 1 0 0 Fine gain register 1 0 1 Offset register A2, A1, A0 These bits are used to decode the DAC channels. A2 A1 A0 Channel Address 0 0 0 DAC A 0 0 1 DAC B 0 1 0 DAC C 0 1 1 DAC D 1 0 0 All DACs Data Data bits. Rev. F | Page 20 of 28
Data Sheet AD5764 FUNCTION REGISTER The function register is addressed by setting the three REG bits to 000. The values written to the address bits and the data bits determine the function addressed. The functions available via the function register are outlined in Table 11 and Table 12. Table 11. Function Register Options REG2 REG1 REG0 A2 A1 A0 DB15:DB6 DB5 DB4 DB3 DB2 DB1 DB0 0 0 0 0 0 0 NOP, data = don’t care 0 0 0 0 0 1 Don’t care Local ground D1 direction D1 value D0 direction D0 value SDO disable offset adjust 0 0 0 1 0 0 Clear, data = don’t care 0 0 0 1 0 1 Load, data = don’t care Table 12. Explanation of Function Register Options Option Description NOP No operation instruction used in readback operations. Local Ground Offset Adjust Set by the user to enable the local ground offset adjust function. Cleared by the user to disable the local ground offset adjust function (default). Refer to the Design Features section for further details. D0/D1 Direction Set by the user to enable D0/D1 as outputs. Cleared by the user to enable D0/D1 as inputs (default). Refer to the Design Features section for further details. D0/D1 Value I/O port status bits. Logic values written to these locations determine the logic outputs on the D0 and D1 pins when configured as outputs. These bits indicate the status of the D0 and D1 pins when the I/O port is active as an input. When enabled as inputs, these bits are don’t cares during a write operation. SDO Disable Set by the user to disable the SDO output. Cleared by the user to enable the SDO output (default). Clear Addressing this function resets the DAC outputs to 0 V in twos complement mode and negative full scale in binary mode. Load Addressing this function updates the data register and consequently the analog outputs. DATA REGISTER The data register is addressed by setting the three REG bits to 010. The DAC address bits select with which DAC channel the data transfer is to take place (see Table 10). The data bits are in Position DB15 to Position DB0, as shown in Table 13. Table 13. Programming the Data Register Bit Map REG2 REG1 REG0 A2 A1 A0 DB15:DB0 0 1 0 DAC address 16-bit DAC data COARSE GAIN REGISTER The coarse gain register is addressed by setting the three REG bits to 011. The DAC address bits select with which DAC channel the data transfer is to take place (see Table 10). The coarse gain register is a 2-bit register and allows the user to select the output range of each DAC, as shown in Table 14 and Table 15. Table 14. Programming the Coarse Gain Register Bit Map REG2 REG1 REG0 A2 A1 A0 DB15: DB2 DB1 DB0 0 1 1 DAC address Don’t care CG1 CG0 Table 15. Output Range Selection Output Range CG1 CG0 ±10 V (Default) 0 0 ±10.2564 V 0 1 ±10.5263 V 1 0 Rev. F | Page 21 of 28
AD5764 Data Sheet FINE GAIN REGISTER OFFSET REGISTER The fine gain register is addressed by setting the three REG bits The offset register is addressed by setting the three REG bits to to 100. The DAC address bits select with which DAC channel 101. The DAC address bits select with which DAC channel the the data transfer is to take place (see Table 10). The fine gain data transfer is to take place (see Table 10). The AD5764 offset register is a 6-bit register and allows the user to adjust the gain register is an 8-bit register and allows the user to adjust the offset of each DAC channel by −32 LSBs to +31 LSBs in 1 LSB of each channel by −16 LSBs to +15.875 LSBs in increments of increments, as shown in Table 16 and Table 17. The adjustment ⅛ LSB, as shown in Table 18 and Table 19. The offset register is made to both the positive full-scale points and the negative coding is twos complement. full-scale points simultaneously, each point being adjusted by ½ of one step. The fine gain register coding is twos complement. Table 16. Programming the Fine Gain Register Bit Map REG2 REG1 REG0 A2 A1 A0 DB15:DB6 DB5 DB4 DB3 DB2 DB1 DB0 1 0 0 DAC address Don’t care FG5 FG4 FG3 FG2 FG1 FG0 Table 17. Fine Gain Register Options Gain Adjustment FG5 FG4 FG3 FG2 FG1 FG0 +31 LSBs 0 1 1 1 1 1 +30 LSBs 0 1 1 1 1 0 … … … … … … … +2 LSBs 0 0 0 0 1 0 +1 LSB 0 0 0 0 0 1 No Adjustment (Default) 0 0 0 0 0 0 −1 LSB 1 1 1 1 1 1 −2 LSBs 1 1 1 1 1 0 … … … … … … … −31 LSBs 1 0 0 0 0 1 −32 LSBs 1 0 0 0 0 0 Table 18. Programming the Offset Register Bit Map REG2 REG1 REG0 A2 A1 A0 DB15:DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 1 0 1 DAC address Don’t care OF7 OF6 OF5 OF4 OF3 OF2 OF1 OF0 Table 19. AD5764 Offset Register Options Offset Adjustment OF7 OF6 OF5 OF4 OF3 OF2 OF1 OF0 +15.875 LSBs 0 1 1 1 1 1 1 1 +15.75 LSBs 0 1 1 1 1 1 1 0 … … … … … … … … … +0.25 LSBs 0 0 0 0 0 0 1 0 +0.125 LSBs 0 0 0 0 0 0 0 1 No Adjustment (Default) 0 0 0 0 0 0 0 0 −0.125 LSBs 1 1 1 1 1 1 1 1 −0.25 LSBs 1 1 1 1 1 1 1 0 … … … … … … … … … −15.875 LSBs 1 0 0 0 0 0 0 1 −16 LSBs 1 0 0 0 0 0 0 0 Rev. F | Page 22 of 28
Data Sheet AD5764 OFFSET AND GAIN ADJUSTMENT WORKED Convert this to a negative twos complement number by inverting EXAMPLE all bits and adding 1 to obtain 11110000, the value that should be programmed to the offset register. Using the information provided in the Fine Gain Register and Offset Register sections, the following worked example demon- Note that this twos complement conversion is not necessary in the strates how the AD5764 functions can be used to eliminate both case of a positive offset adjustment. The value to be programmed to offset and gain errors. Because the AD5764 is factory calibrated, the offset register is simply the binary representation of the offset and gain errors should be negligible. However, errors can adjustment value. be introduced by the system that the AD5764 is operating within; Removing Gain Error for example, a voltage reference value that is not equal to 5 V The AD5764 can eliminate a gain error at negative full-scale introduces a gain error. An output range of ±10 V and twos output in the range of −9.77 mV to +9.46 mV with a step size of complement data coding is assumed. ½ of a 16-bit LSB. Removing Offset Error Calculate the step size of the gain adjustment. The AD5764 can eliminate an offset error in the range of −4.88 mV 20 to +4.84 mV with a step size of ⅛ of a 16-bit LSB. GainAdjustStepSize= =152.59μV 216×2 Calculate the step size of the offset adjustment. Measure the gain error by programming 0x8000 to the data 20 OffsetAdjustStepSize= =38.14μV register and measuring the resulting output voltage. The gain 216×8 error is the difference between this value and −10 V. For this Measure the offset error by programming 0x0000 to the data example, the gain error is −1.2 mV. register and measuring the resulting output voltage. For this Calculate how many gain adjustment steps this value represents. example, the measured value is 614 μV. MeasuredGain Value Calculate the number of offset adjustment steps that this value NumberofSteps= = Gain Step Size represents. 1.2mV MeasuredOffset Value =8 Steps NumberofSteps= = 152.59μV OffsetStepSize The gain error measured is negative (in terms of magnitude); 614μV =16Steps therefore, a positive adjustment of eight steps is required. The 38.14μV gain register is 6 bits wide and the coding is twos complement, the required gain register value can be determined as follows: The offset error measured is positive, therefore, a negative Convert the adjustment value to binary: 001000. adjustment of 16 steps is required. The offset register is eight bits wide and the coding is twos complement. The required The value to be programmed to the gain register is simply this offset register value can be calculated as follows: binary number. Convert the adjustment value to binary: 00010000. Rev. F | Page 23 of 28
AD5764 Data Sheet DESIGN FEATURES ANALOG OUTPUT CONTROL PROGRAMMABLE SHORT-CIRCUIT PROTECTION In many industrial process control applications, it is vital that The short-circuit current of the output amplifiers can be pro- the output voltage be controlled during power-up and during grammed by inserting an external resistor between the ISCC brownout conditions. When the supply voltages are changing, pin and PGND. The programmable range for the current is 500 μA the VOUTx pins are clamped to 0 V via a low impedance path. to 10 mA, corresponding to a resistor range of 120 kΩ to 6 kΩ. The resistor value is calculated as follows: To prevent the output amp being shorted to 0 V during this time, Transmission Gate G1 is also opened (see Figure 35). These condi- 60 R= tions are maintained until the power supplies stabilize and a I SC valid word is written to the data register. At this time, G2 opens and If the ISCC pin is left unconnected, the short-circuit current G1 closes. Both transmission gates are also externally controllable limit defaults to 5 mA. Note that limiting the short-circuit via the reset logic (RSTIN) control input. For instance, if RSTIN current to a small value can affect the slew rate of the output is driven from a battery supervisor chip, the RSTIN input is when driving into a capacitive load; therefore, the value of the driven low to open G1 and close G2 upon power-down or during programmed short circuit should take into account the size of a brownout. Conversely, the on-chip voltage detector output the capacitive load being driven. (RSTOUT) is also available to the user to control other parts of the system. The basic transmission gate functionality is shown DIGITAL I/O PORT in Figure 35. The AD5764 contains a 2-bit digital I/O port (D1 and D0). RSTOUT RSTIN These bits can be configured as inputs or outputs independently, and can be driven or have their values read back via the serial VOLTAGE interface. The I/O port signals are referenced to DVCC and DGND. MONITOR AND When configured as outputs, they can be used as control signals CONTROL to multiplexers or can be used to control calibration circuitry elsewhere in the system. When configured as inputs, the logic G1 signals from limit switches can, for example, be applied to D0 VOUTA G2 and D1 and can be read back via the digital interface. AGNDA 05303-063 LOCAL GROUND OFFSET ADJUST Figure 35. Analog Output Control Circuitry The AD5764 incorporates a local ground offset adjust feature that, when enabled in the function register, adjusts the DAC DIGITAL OFFSET AND GAIN CONTROL outputs for voltage differences between the individual DAC ground The AD5764 incorporates a digital offset adjust function with a pins, AGNDx, and the REFGND pin, ensuring that the DAC ±16 LSB adjust range and 0.125 LSB resolution. The coarse gain output voltages are always with respect to the local DAC ground register allows the user to adjust the AD5764 full-scale output pin. For instance, if Pin AGNDA is at +5 mV with respect to the range. The full-scale output can be programmed to achieve full- REFGND pin and VOUTA is measured with respect to AGNDA, scale ranges of ±10 V, ±10.2564 V, and ±10.5263 V. A fine gain a −5 mV error results, enabling the local ground offset adjust trim is also provided. feature to adjust VOUTA by +5 mV, eliminating the error. Rev. F | Page 24 of 28
Data Sheet AD5764 APPLICATIONS INFORMATION TYPICAL OPERATING CIRCUIT reference and associated buffers. This leads to an overall savings in both cost and board space. Figure 36 shows the typical operating circuit for the AD5764. The only external components needed for this precision 16-bit In Figure 36, AVDD is connected to +15 V and AVSS is connected DAC are a reference voltage source, decoupling capacitors on to −15 V. However, AVDD can operate with supplies from +11.4 V the supply pins and reference inputs, and an optional short- to +16.5 V and AVSS can operate with supplies from −11.4 V to circuit current setting resistor. Because the device incorporates −16.5 V. reference buffers, it eliminates the need for an external bipolar +15V ADR02 2 VIN VOUT 6 GND 4 +15V –15V 10µF 10µF 100nF 100nF 100nF BIN/2sCOMP 32 31 30 29 28 27 26 25 +5V P D S C D C D B SYNC 1 SYNC N/2sCOM AVDAVS N REFGN N REFC REFAAGNDA 24 SCLK 2 SCLK BI VOUTA 23 VOUTA SDIN 3 SDIN VOUTB 22 VOUTB SDO 4 SDO AD5764 AGNDB 21 5 CLR AGNDC 20 LDAC 6 LDAC VOUTC 19 VOUTC D0 7 D0 VOUTD 18 VOUTD D1 8 D1 T AGNDD 17 RSTOU RSTIN DGND DVCCAVDDPGND AVSSISCC 9 10 11 12 13 14 15 16 RSTOUT nF nF 0 0 RSTIN 10µ10F 10 0µF 1 100nF NC = NO CONNECT 10µF +5V +15V –15V 05303-064 Figure 36. Typical Operating Circuit Rev. F | Page 25 of 28
AD5764 Data Sheet Precision Voltage Reference Selection voltage to a voltage other than the nominal. The trim adjust- ment can also be used at temperature to trim out any error. To achieve the optimum performance from the AD5764 over its full operating temperature range, a precision voltage reference Long-term drift is a measure of how much the reference output must be used. Consideration should be given to the selection of voltage drifts over time. A reference with a tight long-term drift a precision voltage reference. The AD5764 has two reference specification ensures that the overall solution remains relatively inputs, REFAB and REFCD. The voltages applied to the refer- stable over its entire lifetime. ence inputs are used to provide a buffered positive and negative The temperature coefficient of a reference output voltage affects reference for the DAC cores. Therefore, any error in the voltage INL, DNL, and TUE. Choose a reference with a tight temperature reference is reflected in the outputs of the device. coefficient specification to reduce the dependence of the DAC There are four possible sources of error to consider when output voltage on ambient conditions. choosing a voltage reference for high accuracy applications: In high accuracy applications, which have a relatively low noise initial accuracy, temperature coefficient of the output voltage, budget, reference output voltage noise needs to be considered. long-term drift, and output voltage noise. Choosing a reference with as low an output noise voltage as Initial accuracy error on the output voltage of an external refer- practical for the system resolution required is important. Precision ence can lead to a full-scale error in the DAC. Therefore, to voltage references such as the ADR435 (XFET® design) produce minimize these errors, a reference with low initial accuracy low output noise in the 0.1 Hz to 10 Hz region. However, as the error specification is preferred. Choosing a reference with an circuit bandwidth increases, filtering the output of the reference output trim adjustment, such as the ADR425, allows a system may be required to minimize the output noise. designer to trim system errors out by setting the reference Table 20. Some Precision References Recommended for Use with the AD5764 Part No. Initial Accuracy (mV Max) Long-Term Drift (ppm Typ) Temp Drift (ppm/°C Max) 0.1 Hz to 10 Hz Noise (μV p-p Typ) ADR435 ±2 40 3 8 ADR425 ±2 50 3 3.4 ADR02 ±5 50 3 10 ADR395 ±5 50 9 8 Rev. F | Page 26 of 28
Data Sheet AD5764 LAYOUT GUIDELINES In any circuit where accuracy is important, careful consideration interfaces because the number of interface lines is kept to a of the power supply and ground return layout helps to ensure the minimum. Figure 37 shows a 4-channel isolated interface to the rated performance. The PCB on which the AD5764 is mounted AD5764 using an ADuM1400. For more information, go to must be designed so that the analog and digital sections are sepa- www.analog.com. rated and confined to certain areas of the board. If the AD5764 is MICROCONTROLLER ADuM1400* icno na nseycstteiomn ,w thhee rceo mnnuelctitpiolen d ise vtoic ebse rmeqaudier ea ta no nAeG pNoiDnt- toon-DlyG. TNhDe SERIAL CLOOCUKT VIA ENCODE DECODE VOA TO SCLK star ground point is established as close as possible to the device. SERIAL DAOTUAT VIB ENCODE DECODE VOB TO SDIN The AD5764 must have ample supply bypassing of 10 μF in parallel with 0.1 μF on each supply, located as close to the package as SYNC OUT VIC ENCODE DECODE VOC TO SYNC paefrofees tcshitbievl etea, sniedtraeileauslml yre rbsiiegsahtdat n tuycppe ea(.gE TaSihRne)s t0a .tn1hd eμ lFdo ecwva ipecfaefc.e iTcttohivre e m1 s0eu rμsitFe sh c iaanvpdeau clocittwoanr sc e *ADDITICOONNATLR POINL SO OUTMITTEVDID FOR CLAERNICTOY.DE DECODE VOD TO LDAC 05303-065 Figure 37. Isolated Interface (ESI), such as the common ceramic types, which provide a low impedance path to ground at high frequencies to handle transient MICROPROCESSOR INTERFACING currents due to internal logic switching. Microprocessor interfacing to the AD5764 is via a serial bus The power supply lines of the AD5764 must be as large a trace that uses a standard protocol that is compatible with micro- as possible to provide low impedance paths and reduce the effects controllers and DSP processors. The communications channel of glitches on the power supply line. Fast switching signals, such as is a 3-wire (minimum) interface consisting of a clock signal, a clocks, must be shielded with digital ground to avoid radiating data signal, and a synchronization signal. The AD5764 requires noise to other parts of the board, and must never be run near a 24-bit data-word with data valid on the falling edge of SCLK. the reference inputs. A ground line routed between the SDIN For all the interfaces, the DAC output update can be performed and SCLK lines helps reduce crosstalk between them (not required automatically when all the data is clocked in, or it can be done on a multilayer board, which has a separate ground plane; however, under the control of LDAC. The contents of the data register it is helpful to separate the lines). It is essential to minimize noise can be read using the readback function. on the reference inputs because it couples through to the DAC EVALUATION BOARD output. Avoid crossover of digital and analog signals. Traces on opposite sides of the board must run at right angles to each other. The AD5764 comes with a full evaluation board to aid designers This reduces the effects of feedthrough on the board. A microstrip in evaluating the high performance of the part with minimum technique is recommended, but not always possible with a double- effort. All that is required with the evaluation board is a power sided board. In this technique, the component side of the board supply and a PC. The AD5764 evaluation kit includes a populated, is dedicated to the ground plane, and signal traces are placed on tested AD5764 PCB. The evaluation board interfaces to the USB the solder side. port of the PC. Software is available with the evaluation board, GALVANICALLY ISOLATED INTERFACE which allows the user to easily program the AD5764. The software runs on any PC that has Microsoft® Windows® 2000/NT/XP In many process control applications, it is necessary to provide installed. an isolation barrier between the controller and the unit being The EVAL-AD5764EB data sheet is available, which gives full controlled to protect and isolate the controlling circuitry from details on the operation of the evaluation board. any hazardous common-mode voltages that may occur. Isocoup- lers provide voltage isolation in excess of 2.5 kV. The serial loading structure of the AD5764 makes it ideal for isolated Rev. F | Page 27 of 28
AD5764 Data Sheet OUTLINE DIMENSIONS 0.75 1.20 MAX 9.00 BSC SQ 0.60 0.45 32 25 1 24 PIN 1 7.00 TOP VIEW BSC SQ 1.05 0° MIN 0.20 (PINS DOWN) 1.00 0.09 0.95 7° 3.5° 8 17 0.15 SEATING 0° 9 16 0.05 PLANE 0C.O08P LMAANXARITY VIEW A 0.80 0.45 BSC VIEW A LEAD PITCH 0.37 0.30 ROTATED 90° CCW COMPLIANTTO JEDEC STANDARDS MS-026-ABA 020607-A Figure 38. 32-Lead Thin Plastic Quad Flat Package [TQFP] (SU-32-2) Dimensions shown in millimeters ORDERING GUIDE Model1 INL Temperature Range Package Description Package Option AD5764ASUZ ±4 LSB max −40°C to +85°C 32-Lead TQFP SU-32-2 AD5764ASUZ-REEL7 ±4 LSB max −40°C to +85°C 32-Lead TQFP SU-32-2 AD5764BSUZ ±2 LSB max −40°C to +85°C 32-Lead TQFP SU-32-2 AD5764BSUZ-REEL7 ±2 LSB max −40°C to +85°C 32-Lead TQFP SU-32-2 AD5764CSUZ ±1 LSB max −40°C to +85°C 32-Lead TQFP SU-32-2 AD5764CSUZ-REEL7 ±1 LSB max −40°C to +85°C 32-Lead TQFP SU-32-2 EVAL-AD5764EBZ Evaluation Board 1 Z = RoHS Compliant Part. ©2006–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05303-0-9/11(F) Rev. F | Page 28 of 28
Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: A nalog Devices Inc.: AD5764BSUZ-REEL7 AD5764ASUZ AD5764ASUZ-REEL7 AD5764BSUZ AD5764CSUZ-REEL7 AD5764CSUZ AD5764SSUZ-EP-RL7