LT1638/LT1639 1.2MHz, 0.4V/µs Over-The-Top Micropower Rail-to-Rail Input and Output Op Amps FEATURES DESCRIPTION n Operates with Inputs Above V+ The LT®1638 is a low p wer dual rail-to-rail input and output n Rail-to-Rail Input and Output operational amplifi er available in the standard 8-pin PDIP n Low Power: 230μA per Amplifi er Max and SO packages as well as the 8-lead MSOP package. The n Gain Bandwidth Product: 1.2MHz LT1639 is a low power quad rail-to-rail input and output n Slew Rate: 0.4V/μs operational amplifi er offered in the standard 14-pin PDIP n High Output Current: 25mA Min and surface mount packages. For space limited applications n Specifi ed on 3V, 5V and ±15V Supplies the LT1638 is available in a 3mm x 3mm x 0.8mm dual n Reverse Battery Protection to 18V fi ne pitch leadless package (DFN). n No Supply Sequencing Problems The LT1638/LT1639 op amps operate on all single and split n High Voltage Gain: 1500V/mV supplies with a total voltage of 2.5V to 44V drawing only n Single Supply Input Range: –0.4V to 44V 170μA of quiescent current per amplifi er. These ampli- n High CMRR: 98dB fi ers are reverse battery protected and draw no current n No Phase Reversal for reverse supply up to 18V. n Available in 14-Lead SO, 8-Lead MSOP and DFN The input range of the LT1638/LT1639 includes both sup- Packages plies, and a unique feature of this device is its capability to operate over the top with either or both of its inputs APPLICATIONS above V+. The inputs handle 44V, both differential and common mode, independent of supply voltage. The input n Battery- or Solar-Powered Systems stage incorporates phase reversal protection to prevent Portable Instrumentation false outputs from occurring when the inputs are below Sensor Conditioning the negative supply. Protective resistors are included in n Supply Current Sensing the input leads so that current does not become excessive n Battery Monitoring when the inputs are forced below the negative supply. n Micropower Active Filters The LT1638/LT1639 can drive loads up to 25mA and still n 4mA to 20mA Transmitters maintain rail-to-rail capability. The op amps are unity-gain L, LT, LTC, LTM, Over-The-Top, Linear Technology and the Linear logo are registered stable and drive all capacitive loads up to 1000pF when trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. optional output compensation is used. TYPICAL APPLICATION Output Voltage vs Input Voltage Over-The-Top® Comparator with 100mV Hysteresis Centered at 0mV 5V 10k 1M VCC V1 VCC 1M VCC + + A B 1/2 LT1638 1/2 LT1638 V0 – 1M – 0V 10k 1M V2 1638/39 TA01 VCC = 5V, VCM = 0V TO 44V, tPD = 27μs 20mV/DIV 1638/39 TA02 16389fg 1

LT1638/LT1639 ABSOLUTE MAXIMUM RATINGS (Note 1) Total Supply Voltage (V+ to V–) ................................44V Specifi ed Temperature Range (Note 4) Input Differential Voltage...........................................44V LT1638C/LT1639C ................................–40°C to 85°C Input Current ........................................................±25mA LT1638I/LT1639I ..................................–40°C to 85°C Output Short-Circuit Duration (Note 2) .........Continuous LT1638H/LT1639H .............................–40°C to 125°C Operating Temperature Range (Note 3) Junction Temperature ..........................................150°C LT1638C/LT1639C ................................–40°C to 85°C DD Package ......................................................125°C LT1638I/LT1639I ..................................–40°C to 85°C Storage Temperature Range ...................–65°C to 150°C LT1638H/LT1639H .............................–40°C to 125°C DD Package .......................................–65°C to 125°C Lead Temperature (Soldering, 10 sec) ..................300°C PIN CONFIGURATION TOP VIEW TOP VIEW OUT A 1 8 V+ OUT A 1 8V+ –IN A 2 7 OUT B –IN A 2 7OUT B A +IN A 3 A 6–IN B +IN A 3 6 –IN B V– 4 B 5+IN B V– 4 B 5 +IN B MS8 PACKAGE 8-LEAD PLASTIC MSOP N8 PACKAGE S8 PACKAGE 8-LEAD PDIP 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 273°C/W TJMAX = 150°C, θJA = 150°C/W (N8) TJMAX = 150°C, θJA = 190°C/W (S8) TOP VIEW TOP VIEW OUT A 1 14 OUT D –IN A 2 13 –IN D OUT A 1 8 V+ +IN A 3 A D 12 +IN D –IN A 2 A 7 OUT B V+ 4 11 V– +IN A 3 6 –IN B B +IN B 5 10 +IN C V– 4 5 +IN B B C –IN B 6 9 –IN C OUT B 7 8 OUT C DD PACKAGE 8-LEAD (3mm (cid:115) 3mm) PLASTIC DFN TJMAX = 125°C, θJA = 43°C/W N PACKAGE S PACKAGE UNDERSIDE METAL INTERNALLY CONNECTED TO V– 14-LEAD PDIP 14-LEAD PLASTIC SO TJMAX = 150°C, θJA = 130°C/W (N) TJMAX = 150°C, θJA = 160°C/W (S) 16389fg 2

LT1638/LT1639 ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LT1638CMS8#PBF LT1638CMS8#TRPBF LTCY 8-Lead Plastic MSOP –40°C to 85°C LT1638IMS8#PBF LT1638IMS8#TRPBF LTCY 8-Lead Plastic MSOP –40°C to 85°C LT1638CDD#PBF LT1638CDD#TRPBF LAAL 8-Lead (3mm × 3mm) Plastic DFN –40°C to 85°C LT1638IDD#PBF LT1638IDD#TRPBF LAAL 8-Lead (3mm × 3mm) Plastic DFN –40°C to 85°C LT1638CN8#PBF LT1638CN8#TRPBF LT1638CN8 8-Lead PDIP –40°C to 85°C LT1638IN8#PBF LT1638IN8#TRPBF LT1638IN8 8-Lead PDIP –40°C to 85°C LT1638CS8#PBF LT1638CS8#TRPBF 1638 8-Lead Plastic SO –40°C to 85°C LT1638IS8#PBF LT1638IS8#TRPBF 1638I 8-Lead Plastic SO –40°C to 85°C LT1638HS8#PBF LT1638HS8#TRPBF 1638H 8-Lead Plastic SO –40°C to 125°C LT1639CN#PBF LT1639CN#TRPBF LT1639CN 14-Lead PDIP –40°C to 85°C LT1639IN#PBF LT1639IN#TRPBF LT1639IN 14-Lead PDIP –40°C to 85°C LT1639CS#PBF LT1639CS#TRPBF LT1639CS 14-Lead Plastic SO –40°C to 85°C LT1639IS#PBF LT1639IS#TRPBF LT1639IS 14-Lead Plastic SO –40°C to 85°C LT1639HS#PBF LT1639HS#TRPBF LT1639HS 14-Lead Plastic SO –40°C to 125°C Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifi cations, go to: http://www.linear.com/tapeandreel/ 16389fg 3

LT1638/LT1639 ELECTRICAL CHARACTERISTICS The l denotes the specifi cations which apply over the specifi ed temperature range, otherwise specifi cations are at T = 25°C. A V = 3V, 0V; V = 5V, 0V; V = V = half supply, unless otherwise noted. (Note 4) S S CM OUT LT1638C/LT1639C, LT1638I/LT1639I SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Input Offset Voltage LT1638 N, S Packages 200 600 μV OS 0°C ≤ T ≤ 70°C l 850 μV A –40°C ≤ T ≤ 85°C l 950 μV A LT1639 N, S Packages 300 700 μV 0°C ≤ T ≤ 70°C l 950 μV A –40°C ≤ T ≤ 85°C l 1050 μV A LT1638 MS8 Package 350 900 μV 0°C ≤ T ≤ 70°C l 1150 μV A –40°C ≤ T ≤ 85°C l 1450 μV A LT1638 DD Package 400 1100 μV 0°C ≤ T ≤ 70°C l 1350 μV A –40°C ≤ T ≤ 85°C l 1450 μV A Input Offset Voltage Drift LT1638/LT1639 N, S Packages l 2 6 μV/°C (Note 9) LT1638MS8, LT1638DD l 2.5 7 μV/°C I Input Offset Current l 1 6 nA OS V = 44V (Note 5) l 2.5 μA CM I Input Bias Current l 20 50 nA B V = 44V (Note 5) l 8 30 μA CM V = 0V 0.1 nA S Input Noise Voltage 0.1Hz to 10Hz 1 μV P-P e Input Noise Voltage Density f = 1kHz 20 nV/√Hz n i Input Noise Current Density f = 1kHz 0.3 pA/√Hz n R Input Resistance Differential 1 2.5 MΩ IN Common Mode, V = 0V to 44V 1.4 5.5 MΩ CM C Input Capacitance 5 pF IN Input Voltage Range l 0 44 V CMRR Common Mode Rejection Ratio V = 0V to V – 1V l 88 98 dB CM CC V = 0V to 44V (Note 8) l 80 88 dB CM A Large-Signal Voltage Gain V = 3V, V = 500mV to 2.5V, R = 10k 200 1500 V/mV VOL S O L 0°C ≤ T ≤ 70°C l 133 V/mV –40°C ≤A T ≤ 85°C l 100 V/mV A V = 5V, V = 500mV to 4.5V, R = 10k 400 1500 V/mV S O L 0°C ≤ T ≤ 70°C l 250 V/mV –40°C ≤A T ≤ 85°C l 200 V/mV A V Output Voltage Swing Low V = 3V, No Load l 3 8 mV OL S V = 3V, I = 5mA l 250 450 mV S SINK V = 5V, No Load l 3 8 mV S V = 5V, I = 10mA l 500 700 mV S SINK V Output Voltage Swing High V = 3V, No Load l 2.94 2.98 V OH S V = 3V, I = 5mA l 2.25 2.40 V S SOURCE V = 5V, No Load l 4.94 4.98 V S V = 5V, I = 10mA l 3.8 4.0 V S SOURCE I Short-Circuit Current (Note 2) V = 3V, Short to GND 10 15 mA SC S V = 3V, Short to V 15 25 mA S CC V = 5V, Short to GND 15 20 mA S V = 5V, Short to V 15 25 mA S CC 16389fg 4

LT1638/LT1639 ELECTRICAL CHARACTERISTICS The l denotes the specifi cations which apply over the specifi ed temperature range, otherwise specifi cations are at T = 25°C. A V = 3V, 0V; V = 5V, 0V; V = V = half supply, unless otherwise noted. (Note 4) S S CM OUT LT1638C/LT1639C, LT1638I/LT1639I SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS PSRR Power Supply Rejection Ratio V = 3V to 12.5V, V = V = 1V l 90 100 dB S CM O Reverse Supply Voltage I = –100μA per Amplifi er l 18 27 V S Minimum Operating Supply Voltage l 2.4 2.7 V I Supply Current per Amplifi er 170 230 μA S (Note 6) l 275 μA GBW Gain Bandwidth Product f = 5kHz 650 1075 kHz (Note 5) 0°C ≤ T ≤ 70°C l 550 kHz A –40°C ≤ T ≤ 85°C l 500 kHz A SR Slew Rate AV = –1, RL = ∞ 0.210 0.38 V/μs (Note 7) 0°C ≤ T ≤ 70°C l 0.185 V/μs A l 0.170 V/μs –40°C ≤ T ≤ 85°C A The l denotes the specifi cations which apply over the specifi ed temperature range, otherwise specifi cations are at T = 25°C. A V = ±15V, V = 0V, V = 0V, unless otherwise noted. (Note 4) S CM OUT LT1638C/LT1639C, LT1638I/LT1639I SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Input Offset Voltage LT1638 N, S Packages 250 800 μV OS 0°C ≤ T ≤ 70°C l 1000 μV A –40°C ≤ T ≤ 85°C l 1100 μV A LT1639 N, S Packages 350 900 μV 0°C ≤ T ≤ 70°C l 1100 μV A –40°C ≤ T ≤ 85°C l 1200 μV A LT1638 MS8 Package 400 1050 μV 0°C ≤ T ≤ 70°C l 1250 μV A –40°C ≤ T ≤ 85°C l 1550 μV A LT1638 DDPackage 450 1250 μV 0°C ≤ T ≤ 70°C l 1450 μV A –40°C ≤ T ≤ 85°C l 1550 μV A Input Offset Voltage Drift LT1638/LT1639 N, S Packages l 2 6 μV/°C (Note 9) LT1638MS8, LT1638DD l 2.5 7 μV/°C I Input Offset Current l 1 6 nA OS I Input Bias Current l 20 50 nA B Input Noise Voltage 0.1Hz to 10Hz 1 μV P-P e Input Noise Voltage Density f = 1kHz 20 nV/√Hz n i Input Noise Current Density f = 1kHz 0.3 pA/√Hz n R Input Resistance Differential 1 2.5 MΩ IN Common Mode, V = –15V to 14V 500 MΩ CM C Input Capacitance 4.5 pF IN Input Voltage Range l –15 29 V CMRR Common Mode Rejection Ratio V = –15V to 29V l 80 88 dB CM A Large-Signal Voltage Gain V = ±14V, R = 10k 200 500 V/mV VOL O L 0°C ≤ T ≤ 70°C l 125 V/mV –40°C ≤A T ≤ 85°C l 100 V/mV A V Output Voltage Swing No Load l ±14.9 ±14.95 V O I = ±10mA l ±13.7 ±14.0 V OUT 16389fg 5

LT1638/LT1639 ELECTRICAL CHARACTERISTICS The l denotes the specifi cations which apply over the specifi ed temperature range, otherwise specifi cations are at T = 25°C. V = ±15V, V = OV, V = OV, unless otherwise noted. (Note 4) A S CM OUT LT1638C/LT1639C, LT1638I/LT1639I SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS I Short-Circuit Current (Note 2) Short to GND 25 40 mA SC 0°C ≤ T ≤ 70°C l 20 mA –40°C ≤A T ≤ 85°C l 15 mA A PSRR Power Supply Rejection Ratio V = ±1.5V to ±22V l 90 100 dB S I Supply Current per Amplifi er 205 280 μA S l 350 μA GBW Gain Bandwidth Product f = 5kHz 750 1200 kHz 0°C ≤ T ≤ 70°C l 650 kHz –40°C ≤A T ≤ 85°C l 600 kHz A SR Slew Rate A = –1, R = ∞, V = ±10V 0.225 0.4 V/μs V L O 0°C ≤ T ≤ 70°C l 0.2 V/μs –40°C ≤A T ≤ 85°C l 0.18 V/μs A The l denotes the specifi cations which apply over the full operating temperature range of –40°C ≤ T ≤ 125°C. A V = 3V, 0V; V = 5V, 0V; V = V = Half Supply unless otherwise specifi ed. (Note 4) S S CM OUT LT1638H/LT1639H SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Input Offset Voltage LT1638S8 200 650 μV OS l 3 mV LT1639S 300 750 μV l 3.2 mV Input Offset Voltage Drift (Note 9) l 15 μV/°C I Input Offset Current l 15 nA OS V = 44V (Note 5) l 10 μA CM I Input Bias Current l 150 nA B V = 44V (Note 5) l 100 μA CM Input Voltage Range l 0.3 44 V CMRR Common Mode Rejection Ratio V = 0.3V to V – 1V l 76 dB CM CC V = 0.3V to 44V l 72 dB CM A Large-Signal Voltage Gain V = 3V, V = 500mV to 2.5V, R = 10k 200 1500 V/mV VOL S O L l 20 V/mV V = 5V, V = 500mV to 4.5V, R = 10k 400 1500 V/mV S O L l 35 V/mV V Output Voltage Swing Low No Load l 15 mV OL I = 5mA l 900 mV SINK VS = 5V, ISINK = 10mA l 1500 mV V Output Voltage Swing High V = 3V, No Load l 2.9 V OH S V = 3V, I = 5mA l 2 V S SOURCE V = 5V, No Load l 4.9 V S V = 5V, I = 10mA l 3.5 V S SOURCE PSRR Power Supply Rejection Ratio V = 3V to 12.5V, V = V = 1V l 80 dB S CM O Minimum Supply Voltage l 2.7 V Reverse Supply Voltage I = –100μA l 18 V S I Supply Current 170 230 μA S (Note 6) l 450 μA GBW Gain Bandwidth Product f = 5kHz 650 1075 kHz (Note 5) l 350 kHz SR Slew Rate A = –1, R = ∞ 0.21 0.38 V/μs V L (Note 7) l 0.1 V/μs 16389fg 6

LT1638/LT1639 ELECTRICAL CHARACTERISTICS The l denotes the specifi cations which apply over the full operating temperature range of –40°C ≤ TA ≤ 125°C, otherwise specifi cations are at T = 25°C. V = ±15V, V = 0V, V = 0V, V = V– unless otherwise specifi ed. (Note 4) A S CM OUT SHDN LT1638H/LT1639H SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Input Offset Voltage LT1638S8 250 850 μV OS l 3.4 mV LT1639S 350 950 μV l 3.6 mV Input Offset Voltage Drift (Note 9) l 15 μV/°C I Input Offset Current l 25 nA OS I Input Bias Current l 250 nA B CMRR Common Mode Rejection Ratio V = –14.7V to 29V l 72 dB CM A Large-Signal Voltage Gain V = ±14V, R = 10k 200 500 V/mV VOL O L l 15 V/mV V Output Voltage Swing No Load l ±14.8 V O I = ±5mA l ±14 V OUT I = ±10mA l ±13.4 V OUT PSRR Power Supply Rejection Ratio V = ±1.5V to ±22V l 84 dB S Minimum Supply Voltage l ±1.35 V I Supply Current 205 280 μA S l 550 μA GBW Gain Bandwidth Product f = 5kHz 750 1200 kHz l 400 kHz SR Slew Rate A = –1, R = ∞, V = ±10V, 0.225 0.4 V/μs V L O Measured at V = ±5V l 0.1 V/μs O Note 1: Stresses beyond those listed under Absolute Maximum Ratings tested or QA sampled at these temperatures. The LT1638I/LT1639I are may cause permanent damage to the device. Exposure to any Absolute guaranteed to meet specifi ed performance from –40°C to 85°C. The Maximum Rating condition for extended periods may affect device LT1638H/LT1639H are guaranteed to meet specifi ed performance from reliability and lifetime. –40°C to 125°C. Note 2: A heat sink may be required to keep the junction temperature Note 5: V = 5V limits are guaranteed by correlation to V = 3V and S S below absolute maximum. This depends on the power supply voltage V = ±15V or V = ±22V tests. S S and how many amplifi ers are shorted. Note 6: V = 3V limits are guaranteed by correlation to V = 5V and S S Note 3: The LT1638C/LT1639C and LT1638I/LT1639I are guaranteed V = ±15V or V = ±22V tests. S S functional over the operating temperature range of –40°C to 85°C The Note 7: Guaranteed by correlation to slew rate at V = ±15V, and GBW at S LT1638H/LT1639H are guaranteed functional over the operating V = 3V and V = ±15V tests. S S temperature range of –40°C to 125°C. Note 8: This specifi cation implies a typical input offset voltage of 2mV at Note 4: The LT1638C/LT1639C are guaranteed to meet specifi ed V = 44V and a maximum input offset voltage of 5mV at V = 44V. CM CM performance from 0°C to 70°C and are designed, characterized and Note 9: This parameter is not 100% tested. expected to meet specifi ed performance from –40°C to 85°C but not 16389fg 7

LT1638/LT1639 TYPICAL PERFORMANCE CHARACTERISTICS Input Bias Current vs Supply Current vs Supply Voltage Minimum Supply Voltage Common Mode Voltage 300 400 10000 R AMPLIFIER (μA)222286420000 TTAA = = 1 2255°°CC SET VOLTAGE (μV) 213000000 RRENT (nA)8600006000 VS = 5VT,A 0 =V –55°C LY CURRENT PE211108640000 TA = –55°C GE IN INPUT OFF––2100000 TTAA = = 1 2255°°CC TA = –55°C INPUT BIAS CU 42000 TTAA == 12255°C°C P N SUP120 CHA–300 –20 100 –400 –40 0 5 10 15 20 25 30 35 40 45 0 1 2 3 4 5 4.0 4.4 4.8 5.2 5.6 44 SUPPLY VOLTAGE (V) TOTAL SUPPLY VOLTAGE (V) COMMON MODE VOLTAGE (V) 1638/39 G01 1638/39 G02 1638/39 G03 Output Saturation Voltage vs Output Saturation Voltage vs Output Saturation Voltage vs Load Current (Output High) Load Current (Output Low) Input Overdrive 1 1 100 VS = ±2.5V VS = ±2.5V VS = ±2.5V GE (V) VOD = 30mV GE (V) VOD = 30mV E (mV) NO LOAD A A G VOLT TA = 125°C VOLT 0.1 TA = 125°C OLTA OUTPUT HIGH ON ON TA = 25°C N V ATI 0.1 TA = 25°C ATI TIO 10 R R A U U R T T U SA SA0.01 AT TPUT TA = –55°C TPUT TA = –55°C PUT S OUTPUT LOW U U T O O U O 0.01 0.001 1 0.001 0.01 0.1 1 10 0.001 0.01 0.1 1 10 0 10 20 30 40 50 60 70 80 90 100 SOURCING LOAD CURRENT (mA) SINKING LOAD CURRENT (mA) INPUT OVERDRIVE (mV) 1638/39 G04 1638/39 G05 1638/39 G06 Noise Voltage Density vs Input Noise Current Density 0.1Hz to 10Hz Noise Voltage Frequency vs Frequency 70 4.5 NOISE VOLTAGE (400nV/DIV) VS = (cid:112)2.5 PUT NOISE VOLTAGE DENSITY (nV/√Hz) 654321000000 PUT NOISE CURRENT DENSITY (pA/√Hz) 43322110........05050505 N N I I 0 0 0 1 2 3 4 5 6 7 8 9 10 1 10 100 1k 1 10 100 1k TIME (SEC) FREQUENCY (Hz) FREQUENCY (Hz) 1638/39 G07 1638/39 G09 1638/39 G08 16389fg 8

LT1638/LT1639 TYPICAL PERFORMANCE CHARACTERISTICS Gain and Phase Shift vs Gain Bandwidth Product vs Frequency Temperature Slew Rate vs Temperature 80 100 1500 0.60 70 VS = ±2.5V 90 f = 1kHz 60 80 kHz)1400 0.55 RISING, VS = ±15V GAIN (dB) 3451200000 GAIN PHASE 4673500000PHASE SHIFT (DEG) ANDWIDTH PRODUCT (1111321000000000 VS = ±15V SLEW RATE (V/μs)0000....54430505 FALRLIISNINGG, V, SV S= =± 2±.25.V5V B 0 20 GAIN 900 VS = ±2.5V 0.30 FALLING, VS = ±15V –10 10 –20 0 800 0.25 1 10 100 1000 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 FREQUENCY (kHz) TEMPERATURE (°C) TEMPERATURE (°C) 1638/39 G12 1638/39 G13 1638/39 G14 Gain Bandwidth Product and Gain Bandwidth Product and Phase Margin vs Supply Voltage Phase Margin vs Load Resistance PSRR vs Frequency 1500 60 1500 60 90 BANDWIDTH PRODUCT (kHz)111243000000 GPAHIANS BEA MNADRWGIIDNTH 354000PHASE MARGIN (DEG) BANDWIDTH PRODUCT (kHz)11111432100000000000 PHASE MARGINGPRAIOND ARVfBU =SVFAC N=1==T k DR±–HW21Gz. I5=DV 1T0H0k 5432100000PHASE MARGIN (DEG) SUPPLY REJECTION RATIO (dB) 87654320000000 NEGATIVE SUPPLPYOSITIVE SUVPSP =L ±Y2.5V GAIN 1100 20 GAIN 900 0 WER 10 O 0 P 1000 10 800 –10 –10 0 5 10 15 20 25 30 35 40 45 1 10 100 1 10 100 1000 TOTAL SUPPLY VOLTAGE (V) LOAD RESISTANCE (kΩ) FREQUENCY (kHz) 1638/39 G15 1638/39 G17 1638/39 G16 CMRR vs Frequency Channel Separation vs Frequency Output Impedance vs Frequency 120 130 10k B)110 VS = ±15V VS = ±15V VS = ±2.5V ATIO (d100 dB) 120 Ω) 1k AV = 10 DE REJECTION R 98760000 EL SEPARATION ( 11109000 UT IMPEDANCE (10100 AV = 100 O N P N M 50 HAN 80 OUT AV = 1 MO 40 C 1 M 70 O 30 C 20 60 0.1 1 10 100 1000 0.1 1 10 100 0.1 1 10 100 1000 FREQUENCY (kHz) FREQUENCY (kHz) FREQUENCY (kHz) 1638/39 G18 1638/39 G19 1638/39 G20 16389fg 9

LT1638/LT1639 TYPICAL PERFORMANCE CHARACTERISTICS Settling Time to 0.1% vs Capacitive Load Handling, Undistorted Output Swing Output Step Overshoot vs Capacitive Load vs Frequency 10 100 35 68 VS = ±15V AV = 1 9800 VVISSCO MU= R=5C V2E,. 5=0V V150μA 30 VS = ±15V DRILS =T O20RkTION ≤ 1% TEP (V) 24 AV = –1 OT (%) 7600 NG (V)P-P 2250 TPUT S –20 ERSHO 5400 AV = 1 AV = 5 UT SWI 15 U V P O –4 O 30 UT 10 AV = –1 AV = 10 O –6 AV = 1 20 5 VS = ±2.5V –8 10 –10 0 0 0 5 10 15 20 25 30 35 10 100 1000 10000 0.1 1 10 100 SETTLING TIME (μs) CAPACITIVE LOAD (pF) FREQUENCY (kHz) 1638/39 G21 1638/39 G22 1638/39 G23 Total Harmonic Distortion + Noise Total Harmonic Distortion + Noise Total Harmonic Distortion + Noise vs Frequency vs Load Resistance vs Output Voltage 10 10 10 VS = 3V, 0V VS = 3V TOTAL RL = 10k, f = 1kHz VOUT = 2VP-P AV = 1 VCM = HALF SUPPLY VCM = 1.2V VIN = 2VP-P AT 1kHz AV = –1, VS = ±1.5V 1 RL = 20k 1 1 AV = –1, VS = 3V, 0V THD + NOISE (%) 0.1 THD + NOISE (%) 0.1 VSVV =SIN 3= =V ± ,± 101.V5VV THD + NOISE (%) 0.1 AAVV == 11,, VVSS == ±31V.,5 0VV 0.01 AV = –1 0.01 VIN = 0.5V TO 2.5V 0.01 AV = 1 VS = 3V, 0V VIN = 0.2V TO 2.2V 0.001 0.001 0.001 0.01 0.1 1 10 100 0.1 1 10 100 0 1 2 3 FREQUENCY (kHz) LOAD RESISTANCE TO GROUND (kΩ) OUTPUT VOLTAGE (VP-P) 1638/39 G24 1638/39 G25 1638/39 G26 Open-Loop Gain Large-Signal Response Small-Signal Response V) V/DI VS = ±15V μ 0 5 GE ( RL = 2k TA RL = 10k L O V T SE RL = 50k F F O T U P N N I GE I VS = ±15V 1638/39 G28 VS = ±15V 1638/39 G29 AN AV = 1 AV = 1 CH CL = 15pF –20V –10V 0V 10V 20V OUTPUT VOLTAGE (5V/DIV) 1638/39 G27 16389fg 10

LT1638/LT1639 APPLICATIONS INFORMATION Supply Voltage The inputs are protected against excursions of 2V below V– by an internal 1k resistor in series with each input and The positive supply pin of the LT1638/LT1639 should be a diode from the input to the negative supply. If the inputs bypassed with a small capacitor (typically 0.1μF) within an can go more than 2V below V–, an additional external inch of the pin. When driving heavy loads an additional 4.7μF resistor is required. A 10k resistor will protect the input electrolytic capacitor should be used. When using split against excursions as much as 10V below V–. The input supplies, the same is true for the negative supply pin. stage of the LT1638/LT1639 incorporates phase reversal The LT1638/LT1639 are protected against reverse battery protection to prevent the output from phase reversing for voltages up to 18V. In the event a reverse battery condition inputs below V–. There are no clamping diodes between occurs, the supply current is less than 1nA. the inputs and the maximum differential input voltage is The LT1638/LT1639 can be shut down by removing V+. 44V. In this condition the input bias current is less than 0.1nA, Output even if the inputs are 44V above the negative supply. The output of the LT1638/LT1639 can swing within 20mV When operating the LT1638/LT1639 on total supplies of of the positive rail with no load, and within 3mV of the 10V or more, the supply must not be brought up faster negative rail with no load. When monitoring voltages than 1V/μs. Increasing the bypass capacitor and/or add- within 20mV of the positive rail or within 3mV of the ing a small resistor in series with the supply will limit the negative rail, gain should be taken to keep the output from rise time. clipping. The LT1638/LT1639 are capable of sinking and sourcing over 40mA on ±15V supplies; sourcing current Inputs capability is reduced to 20mA at 5V total supplies as noted The LT1638/LT1639 have two input stages, NPN and PNP in the electrical characteristics. (see the Simplifi ed Schematic), resulting in three distinct The LT1638/LT1639 are internally compensated to drive operating regions as shown in the Input Bias Current vs at least 200pF of capacitance under any output loading Common Mode typical performance curve. conditions. A 0.22μF capacitor in series with a 150Ω For input voltages about 0.8V or more below V+, the PNP resistor between the output and ground will compensate input stage is active and the input bias current is typically these amplifi ers for larger capacitive loads, up to 1000pF, –20nA. When the input common mode voltage is within at all output currents. 0.5V of the positive rail, the NPN stage is operating and the input bias current is typically 40nA. Increases in tem- Optional Output Compensation for perature will cause the voltage at which operation switches Capacitive Loads Greater than 200pF from the PNP input stage to the NPN input stage to move towards V+. The input offset voltage of the NPN stage is VIN + untrimmed and is typically 600μV. LT1638 A Schottky diode in the collector of each NPN transistor – 1000pF allow the LT1638/LT1639 to operate over the top, with either or both of its inputs above V+. At about 0.3V above 0.22μF V+ the NPN input transistor is fully saturated and the 150Ω input bias current is typically 8μA at room temperature. The input offset voltage is typically 2mV when operating Distortion above V+. The LT1638/LT1639 will operate with its inputs 44V above V– regardless of V+. There are two main contributors of distortion in op amps: output crossover distortion as the output transitions from sourcing to sinking current and distortion caused by 16389fg 11

LT1638/LT1639 APPLICATIONS INFORMATION nonlinear common mode rejection. If the op amp is current and with the input voltage swing between ground operating inverting there is no common mode induced and (V+ – 0.8V). See the Typical Performance Character- distortion. If the op amp is operating in the PNP input istics curves. stage (input is not within 0.8V of V+), the CMRR is very good, typically 98dB. When the LT1638 switches between Gain input stages there is signifi cant nonlinearity in the CMRR. The open-loop gain is almost independent of load when Lower load resistance increases the output crossover the output is sourcing current. This optimizes perfor- distortion, but has no effect on the input stage transition mance in single supply applications where the load is distortion. For lowest distortion the LT1638/LT1639 should returned to ground. The typical performance curve of be operated single supply, with the output always sourcing Open-Loop Gain for various loads shows the details. TYPICAL APPLICATIONS VCC With 1.2MHz bandwidth, Over-The-Top capability, reverse- R5 100k battery protection and rail-to-rail input and output features, + the LT1638/LT1639 are ideal candidates for general purpose 1/4 LT1639 applications. – LT1634-1.2V D1 R3 D2 The lowpass slope limiting fi lter in Figure 1 limits the 100k maximum dV/dT (not frequency) that it passes. When the input signal differs from the output by one forward diode – drop, D1 or D2 will turn on. With a diode on, the voltage R1 1/4 LT1639 VOUT across R2 will be constant and a fi xed current, V /R2, 1k R2 DIODE VIN + will fl ow through capacitor C1, charging it linearly instead C1 of exponentially. The maximum slope that the circuit will R4 100k LT1634-1.2V pass is equal to V divided by (R2)(C1). No matter DIODE how fast the input changes the output will never change D3 D4 – any faster than the dV/dT set by the diodes and (R2)(C). 1/4 LT1639 FOR R2 = 50k, C1 = 500pF, + D1 MAXIMUM SLOPE = 0.048V/μs d 1.2V R6 D2 dtVOUT = (R2)(C1) 100k 1638/39 F02 D1 TO D4 = IN4148 VEE R1 R2 VIN + Response of Slope Limiting Filter ddtVOUT(MAX) = (R2V)D(C1) C1 1/2 LT1638 VOUT – FOR R1 = 10k, R2 = 100k, C1 = 1000pF d dtVOUT(MAX) = 0.006V/μs 1638/39 F01 VOUT Figure 1. Lowpass Slope Limiting Filter A modifi cation of this application is shown in Figure 2 using references instead of diodes to set the maximum slope. By VIN using references, the slope is independent of temperature. A scope photo shows a 1V , 2kHz input signal with a 2V P-P pulse added to the sine wave; the circuit passes the 2kHz 1638/39 TA02 signal but limits the slope of the pulse. Figure 2. Lowpass Slope Limiting Filter with 0 TC 16389fg 12

LT1638/LT1639 TYPICAL APPLICATIONS The application in Figure 3 utilizes the Over-The-Top The Figure 4 application uses the LT1638 in conjunction capabilities of the LT1638. The 0.2Ω resistor senses the with the LT1634 micropower shunt reference. The supply load current while the op amp and NPN transistor form a current of the op amp also biases the reference. The drop closed loop making the collector current of Q1 across resistor R1 is fi xed at 1.2V generating an output proportional to the load current. As a convenient monitor, current equal to 1.2V/R1. the 2k load resistor converts the current into a voltage. The positive supply rail, V+, is not limited to the 5V supply of the op amp and could be as high as 44V. V+ 200Ω VCC VCC 5V LT1634-1.2 R1 0.2Ω + Q1 200Ω 1/2 LT1638 2N3904 + – 0V TO 4.3V 1/2 LT1638 IOUT = 1R.21V LOAD ILOAD 2k – IOUT VOUT = (2Ω)(ILOAD) 1638/39 F03 1638/39 F04 Figure 3. Positive Supply Rail Current Sense Figure 4. Current Source SIMPLIFIED SCHEMATIC V+ Q1 Q2 Q3 Q22 D1 D2 D3 R1 6k R2 Q19 1k Q4 –IN Q17 Q20 + R3 Q7 Q8 Q11 Q12 OUT 1k Q16 Q18 10μA +IN Q15 Q9 Q10 Q13 Q14 Q21 R4 R5 Q5 Q6 D4 D5 8k 8k V– ONE AMPLIFIER 1638/39 SS 16389fg 13

LT1638/LT1639 PACKAGE DESCRIPTION Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. DD Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698 Rev C) R = 0.125 0.40 (cid:112) 0.10 TYP 5 8 0.70 (cid:112)0.05 3.5 (cid:112)0.05 1.65 (cid:112)0.05 3.00 (cid:112)0.10 1.65 (cid:112) 0.10 2.10 (cid:112)0.05 (2 SIDES) (4 SIDES) (2 SIDES) PIN 1 PACKAGE TOP MARK OUTLINE (NOTE 6) (DD8) DFN 0509 REV C 4 1 0.25 (cid:112) 0.05 0.200 REF 0.75 (cid:112)0.05 0.25 (cid:112) 0.05 0.50 0.50 BSC BSC 2.38 (cid:112)0.10 2.38 (cid:112)0.05 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON TOP AND BOTTOM OF PACKAGE MS8 Package 8-Lead Plastic MSOP (Reference LTC DWG # 05-08-1660 Rev F) 3.00 (cid:112) 0.102 (.118 (cid:112) .004) 0.52 (NOTE 3) 8 7 6 5 (.0205) REF 3.00 (cid:112) 0.102 4.90 (cid:112) 0.152 0.889 (cid:112) 0.127 0.254 DETAIL “A” (.193 (cid:112) .006) (.118 (cid:112) .004) (.035 (cid:112) .005) (NOTE 4) (.010) 0(cid:111) – 6(cid:111) TYP GAUGE PLANE 5.23 1 2 3 4 3.20 – 3.45 (.206) 0.53 (cid:112) 0.152 MIN (.126 – .136) (.021 (cid:112) .006) 1.10 0.86 (.043) (.034) DETAIL “A” MAX REF 0.18 0.42 (cid:112) 0.038 0.65 (.007) (.0165 (cid:112) .0015) (.0256) SEATING TYP BSC PLANE 0.22 – 0.38 0.1016 (cid:112) 0.0508 RECOMMENDED SOLDER PAD LAYOUT (.009 – .015) (.004 (cid:112) .002) NOTE: TYP 0.65 MSOP (MS8) 0307 REV F (.0256) 1. DIMENSIONS IN MILLIMETER/(INCH) BSC 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 16389fg 14

LT1638/LT1639 PACKAGE DESCRIPTION Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. N8 Package 8-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .400* (10.160) MAX 8 7 6 5 .300 – .325 .045 – .065 .130 ± .005 (7.620 – 8.255) (1.143 – 1.651) (3.302 ± 0.127) .255 ± .015* (6.477 ± 0.381) .065 (1.651) 1 2 3 4 .008 – .015 TYP (0.203 – 0.381) .120 N8 1002 (3.048) .020 +.035 MIN (0.508) .325 ( –.015 ) .100 .018 ± .003 MIN +0.889 8.255 (2.54) (0.457 ± 0.076) –0.381 BSC NOTE: INCHES 1. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .189 – .197 .045 (cid:112).005 (4.801 – 5.004) .050 BSC NOTE 3 8 7 6 5 .245 MIN .160 (cid:112).005 .150 – .157 .228 – .244 (3.810 – 3.988) (5.791 – 6.197) NOTE 3 .030 (cid:112).005 TYP 1 2 3 4 RECOMMENDED SOLDER PAD LAYOUT .010 – .020 (cid:115) 45(cid:111) .053 – .069 (0.254 – 0.508) (1.346 – 1.752) .004 – .010 .008 – .010 (0.203 – 0.254) 0(cid:111)– 8(cid:111) TYP (0.101 – 0.254) .016 – .050 .014 – .019 .050 (0.406 – 1.270) (0.355 – 0.483) (1.270) NOTE: INCHES TYP BSC 1. DIMENSIONS IN (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) SO8 0303 16389fg 15

LT1638/LT1639 PACKAGE DESCRIPTION Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. N Package 14-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .770* (19.558) MAX 14 13 12 11 10 9 8 .255 ± .015* (6.477 ± 0.381) 1 2 3 4 5 6 7 .300 – .325 .130 ± .005 .045 – .065 (7.620 – 8.255) (3.302 ± 0.127) (1.143 – 1.651) .020 (0.508) MIN .065 .008 – .015 (1.651) (0.203 – 0.381) TYP +.035 .325–.015 .120 .005 .018 ± .003 (8.255+–00..838891) (3M.0I4N8) (0M.1I2N7) (.21.0504) (0.457 ± 0N.1047 1160)3 BSC NOTE: INCHES 1. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) S Package 14-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .337 – .344 .045 ±.005 (8.560 – 8.738) .050 BSC NOTE 3 14 13 12 11 10 9 8 N N .245 MIN .160 ±.005 .228 – .244 .150 – .157 (5.791 – 6.197) (3.810 – 3.988) NOTE 3 1 2 3 N/2 N/2 .030 ±.005 TYP RECOMMENDED SOLDER PAD LAYOUT 1 2 3 4 5 6 7 .010 – .020 (cid:115) 45° .053 – .069 (0.254 – 0.508) NOTE: (1.346 – 1.752) 1. DIMENSIONS IN INCHES .008 – .010 .004 – .010 (MILLIMETERS) (0.203 – 0.254) 0° – 8° TYP (0.101 – 0.254) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS .016 – .050 .014 – .019 .050 SHALL NOT EXCEED .006" (0.15mm) (0.406 – 1.270) (0.355 – 0.483) (1.270) TYP BSC 1S164 3058092fg 16

LT1638/LT1639 REVISION HISTORY (Revision history begins at Rev E) REV DATE DESCRIPTION PAGE NUMBER E 06/10 Updates to Supply Voltage section 11 F 09/10 Units on x-axis of G24 changed from Hz to kHz 10 G 10/11 Updated θJA values for MS8 and DD packages in Pin Confi guration 2 Corrected part numbers and revised column title to Specifi ed Temperature Range in Order Information 3 Deleted Note 10 from Electrical Characteristics 7 16389fg Information furnished by Linear Technology Corporation is believed to be accurate and reliable. 17 However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.

LT1638/LT1639 TYPICAL APPLICATION The battery monitor in Figure 5 also demonstrates the loop when the battery is discharging. The current through LT1638’s ability to operate with its inputs above the Q1 or Q2 is proportional to the current in R and this cur- S positive rail. In this application, a conventional amplifi er rent fl ows into R and is converted into a voltage. Amp G would be limited to a battery voltage between 5V and D buffers and amplifi es the voltage across R . Amp C G ground, but the LT1638 can handle battery voltages as compares the output of Amp A and Amp B to determine high as 44V. When the battery is charging, Amp B senses the polarity of current through R . The scale factor for S the voltage drop across R . The output of Amp B causes V with S1 open is 1V/A. With S1 closed the scale S OUT Q2 to drain suffi cient current through R to balance the factor is 1V/100mA and currents as low as 500μA can B input of Amp B. Likewise, Amp A and Q1 form a closed be measured. CHARGER RS, 0.2Ω RA, 2k + Q1 VOLTAGE 2N3904 A + IBATT RA', 2k 1/4 LT1639 C – 1/4 LT1639 LOGIC – RB, 2k + Q2 LOGIC HIGH (5V) = CHARGING 2N3904 LOGIC LOW (0V) = DISCHARGING B RB', 2k 1/4 LT1639 – + LOAD + VBATT = 12V 1R0Gk 1/4 LDT1639 VOUT – S1 10k 90.9k 1638/39 F05 IBATT = V O U T = V O U T AMPS S1 = OPEN, GAIN = 1 RA = RB (RS)(RG/RA)(GAIN) GAIN S1 = CLOSED, GAIN = 10 VS = 5V, 0V Figure 5. Battery Monitor RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1078/LT1079 Dual/Quad 55μA Max, Single Supply, Precision Op Amps Input/Output Common Mode Includes Ground, 70μV V OS(MAX) LT2078/LT2079 and 2.5μV/°C Drift (Max), 200kHz GBW, 0.07V/μs Slew Rate LT1178/LT1179 Dual/Quad 17μA Max, Single Supply, Precison Op Amps Input/Output Common Mode Includes Ground, 70μV V OS(MAX) LT2178/LT2179 and 4μV/°C Drift (Max), 85kHz GBW, 0.04V/μs Slew Rate LT1366/LT1367 Dual/Quad Precision, Rail-to-Rail Input and Output Op Amps 475μV V , 500V/mV A , 400kHz GBW OS(MAX) VOL(MIN) LT1490/LT1491 Dual/Quad Over-The-Top Micropower, Rail-to-Rail Input and Single Supply Input Range: –0.4V to 44V, Micropower 50μA Output Op Amps per Amplifi er, Rail-to-Rail Input and Output, 200kHz GBW LT1636 Single Over-The-Top Micropower Rail-to-Rail Input and Output 55μA Supply Current, V Extends 44V above V , CM EE Op Amp Independent of V ; MSOP Package, Shutdown Function CC 16389fg 18 Linear Technology Corporation LT 1011 REV G • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 1998