LT1763 Series 500mA, Low Noise, LDO Micropower Regulators FeaTures DescripTion n Low Noise: 20µVRMS (10Hz to 100kHz) The LT®1763 series are micropower, low noise, low dropout n Output Current: 500mA regulators. The devices are capable of supplying 500mA of n Low Quiescent Current: 30µA output current with a dropout voltage of 300mV. Designed n Wide Input Voltage Range: 1.8V to 20V for use in battery-powered systems, the low 30µA quiescent n Low Dropout Voltage: 300mV current makes them an ideal choice. Quiescent current is n Very Low Shutdown Current: < 1µA well controlled; it does not rise in dropout as it does with n No Protection Diodes Needed many other regulators. n Fixed Output Voltages: 1.5V, 1.8V, 2.5V, 3V, 3.3V, 5V A key feature of the LT1763 regulators is low output noise. n Adjustable Output from 1.22V to 20V With the addition of an external 0.01µF bypass capacitor, n Stable with 3.3µF Output Capacitor output noise drops to 20µV over a 10Hz to 100kHz n Stable with Aluminum, Tantalum or Ceramic RMS bandwidth. The LT1763 regulators are stable with output Capacitors capacitors as low as 3.3µF. Small ceramic capacitors can n Reverse Battery Protection be used without the series resistance required by other n No Reverse Current regulators. n Overcurrent and Overtemperature Protected n 8-Lead SO and 12-Lead (4mm × 3mm) DFN Internal protection circuitry includes reverse battery Packages protection, current limiting, thermal limiting and reverse current protection. The parts come in fixed output voltages applicaTions of 1.5V, 1.8V, 2.5V, 3V, 3.3V and 5V, and as an adjustable device with a 1.22V reference voltage. The LT1763 regu- n Cellular Phones lators are available in 8-lead SO and 12-lead, low profile n Battery-Powered Systems (4mm × 3mm × 0.75mm) DFN packages. n Noise-Sensitive Instrumentation Systems L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6144250, 6118263. Typical applicaTion Dropout Voltage 3.3V Low Noise Regulator 400 350 VIN IN OUT + 32.03µVV ARMT S5 0N0OmISAE mV) 300 3.7V2 T0OV 1µF SENSE 10µF AGE ( 250 LT1763-3.3 0.01µF LT O 200 V SHDN BYP T GND OU 150 P O 1763 TA01 DR 100 50 0 0 100 200 300 400 500 OUTPUT CURRENT (mA) 1763 TA02 1763fh 1 For more information www.linear.com/LT1763

LT1763 Series absoluTe MaxiMuM raTings (Note 1) IN Pin Voltage ........................................................±20V Operating Junction Temperature Range (Note 2) OUT Pin Voltage .....................................................±20V C, I Grade ...........................................–40°C to 125°C Input to Output Differential Voltage ........................±20V MP Grade ...........................................–55°C to 125°C SENSE Pin Voltage ............................................... ±20V Storage Temperature Range ADJ Pin Voltage ...................................................... ±7V S8 Package ........................................–65°C to 150°C BYP Pin Voltage .....................................................±0.6V DFN Package ......................................–65°C to 150°C SHDN Pin Voltage ................................................ ±20V Lead Temperature (Soldering, 10 sec) Output Short-Circuit Duration ........................ Indefinite S8 Package .......................................................300°C pin conFiguraTion TOP VIEW NC 1 12 NC TOP VIEW OUT 2 11 IN OUT 1 8 IN OUT 3 10 IN 13 SENSE/ADJ* 2 7 GND NC 4 GND 9 NC GND 3 6 GND SENSE/ADJ* 5 8 SHDN BYP 4 5 SHDN BYP 6 7 GND S8 PACKAGE 8-LEAD PLASTIC SO DE PACKAGE 12-LEAD (4mm × 3mm) PLASTIC DFN TJMAX = 150°C, θJA = 70°C/W, θJC = 35°C/W TJMAX = 125°C, θJA = 40°C/W, θJC = 5°C/W *PIN 2: SENSE FOR LT1763-1.5/LT1763-1.8/LT1763-2.5/LT1763-3/LT1763-3.3/LT1763-5 EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB ADJ FOR LT1763 *PIN 5: SENSE FOR LT1763-1.5/LT1763-1.8/LT1763-2.5/LT1763-3/LT1763-3.3/LT1763-5 SEE THE APPLICATIONS INFORMATION SECTION. ADJ FOR LT1763 SEE THE APPLICATIONS INFORMATION SECTION. orDer inForMaTion LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT1763CDE#PBF LT1763CDE#TRPBF 1763 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763IDE#PBF LT1763IDE#TRPBF 1763 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE#PBF LT1763MPDE#TRPBF 1763 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CDE-1.5#PBF LT1763CDE-1.5#TRPBF 76315 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763IDE-1.5#PBF LT1763IDE-1.5#TRPBF 76315 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE-1.5#PBF LT1763MPDE-1.5#TRPBF 76315 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CDE-1.8#PBF LT1763CDE-1.8#TRPBF 76318 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C 1763fh 2 For more information www.linear.com/LT1763

LT1763 Series orDer inForMaTion LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT1763IDE-1.8#PBF LT1763IDE-1.8#TRPBF 76318 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE-1.8#PBF LT1763MPDE-1.8#TRPBF 76318 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CDE-2.5#PBF LT1763CDE-2.5#TRPBF 76325 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763IDE-2.5#PBF LT1763IDE-2.5#TRPBF 76325 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE-2.5#PBF LT1763MPDE-2.5#TRPBF 76325 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CDE-3#PBF LT1763CDE-3#TRPBF 17633 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763IDE-3#PBF LT1763IDE-3#TRPBF 17633 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE-3#PBF LT1763MPDE-3#TRPBF 17633 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CDE-3.3#PBF LT1763CDE-3.3#TRPBF 76333 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763IDE-3.3#PBF LT1763IDE-3.3#TRPBF 76333 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE-3.3#PBF LT1763MPDE-3.3#TRPBF 76333 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CDE-5#PBF LT1763CDE-5#TRPBF 17635 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763IDE-5#PBF LT1763IDE-5#TRPBF 17635 12-Lead (4mm × 3mm) Plastic DFN –40°C to 125°C LT1763MPDE-5#PBF LT1763MPDE-5#TRPBF 17635 12-Lead (4mm × 3mm) Plastic DFN –55°C to 125°C LT1763CS8#PBF LT1763CS8#TRPBF 1763 8-Lead Plastic SO –40°C to 125°C LT1763IS8#PBF LT1763IS8#TRPBF 1763 8-Lead Plastic SO –40°C to 125°C LT1763MPS8#PBF LT1763MPS8#TRPBF 1763MP 8-Lead Plastic SO –55°C to 125°C LT1763CS8-1.5#PBF LT1763CS8-1.5#TRPBF 176315 8-Lead Plastic SO –40°C to 125°C LT1763IS8-1.5#PBF LT1763IS8-1.5#TRPBF 176315 8-Lead Plastic SO –40°C to 125°C LT1763CS8-1.8#PBF LT1763CS8-1.8#TRPBF 176318 8-Lead Plastic SO –40°C to 125°C LT1763IS8-1.8#PBF LT1763IS8-1.8#TRPBF 176318 8-Lead Plastic SO –40°C to 125°C LT1763CS8-2.5#PBF LT1763CS8-2.5#TRPBF 176325 8-Lead Plastic SO –40°C to 125°C LT1763IS8-2.5#PBF LT1763IS8-2.5#TRPBF 176325 8-Lead Plastic SO –40°C to 125°C LT1763MPS8-2.5#PBF LT1763MPS8-2.5#TRPBF 176325 8-Lead Plastic SO –55°C to 125°C LT1763CS8-3#PBF LT1763CS8-3#TRPBF 17633 8-Lead Plastic SO –40°C to 125°C LT1763IS8-3#PBF LT1763IS8-3#TRPBF 17633 8-Lead Plastic SO –40°C to 125°C LT1763CS8-3.3#PBF LT1763CS8-3.3#TRPBF 176333 8-Lead Plastic SO –40°C to 125°C LT1763IS8-3.3#PBF LT1763IS8-3.3#TRPBF 176333 8-Lead Plastic SO –40°C to 125°C LT1763CS8-5#PBF LT1763CS8-5#TRPBF 17635 8-Lead Plastic SO –40°C to 125°C LT1763IS8-5#PBF LT1763IS8-5#TRPBF 17635 8-Lead Plastic SO –40°C to 125°C LT1763MPS8-5#PBF LT1763MPS8-5#TRPBF 17635 8-Lead Plastic SO –55°C to 125°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on nonstandard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ 1763fh 3 For more information www.linear.com/LT1763

LT1763 Series elecTrical characTerisTics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25°C. (Note 2) A PARAMETER CONDITIONS MIN TYP MAX UNITS Minimum Operating Voltage C, I Grade: I = 500mA (Notes 3, 11) l 1.8 2.3 V LOAD MP Grade: I = 500mA (Notes 3, 11) l 1.8 2.35 V LOAD Regulated Output Voltage LT1763-1.5 V = 2V, I = 1mA 1.485 1.5 1.515 V IN LOAD (Note 4) 2.5V < V < 20V, 1mA < I < 500mA l 1.462 1.5 1.538 V IN LOAD LT1763-1.8 V = 2.3V, I = 1mA 1.782 1.8 1.818 V IN LOAD 2.8V < V < 20V, 1mA < I < 500mA l 1.755 1.8 1.845 V IN LOAD LT1763-2.5 V = 3V, I = 1mA 2.475 2.5 2.525 V IN LOAD 3.5V < V < 20V, 1mA < I < 500mA l 2.435 2.5 2.565 V IN LOAD LT1763-3 V = 3.5V, I = 1mA 2.970 3 3.030 V IN LOAD 4V < V < 20V, 1mA < I < 500mA l 2.925 3 3.075 V IN LOAD LT1763-3.3 V = 3.8V, I = 1mA 3.267 3.3 3.333 V IN LOAD 4.3V < V < 20V, 1mA < I < 500mA l 3.220 3.3 3.380 V IN LOAD LT1763-5 V = 5.5V, I = 1mA 4.950 5 5.050 V IN LOAD 6V < V < 20V, 1mA < I < 500mA l 4.875 5 5.125 V IN LOAD ADJ Pin Voltage LT1763 V = 2.2V, I = 1mA 1.208 1.220 1.232 V IN LOAD (Notes 3, 4) C, I Grade: 2.3V < V < 20V, 1mA < I < 500mA l 1.190 1.220 1.250 V IN LOAD MP Grade: 2.35V < V < 20V, 1mA < I < 500mA l 1.190 1.220 1.250 V IN LOAD Line Regulation LT1763-1.5 C, I Grade: ∆V = 2V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763-1.5 MP Grade: ∆V = 2.1V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763-1.8 ∆V = 2.3V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763-2.5 ∆V = 3V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763-3 ∆V = 3.5V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763-3.3 ∆V = 3.8V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763-5 ∆V = 5.5V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763 (Note 3) C, I Grade: ∆V = 2V to 20V, I = 1mA l 1 5 mV IN LOAD LT1763 (Note 3) MP Grade: ∆V = 2.1V to 20V, I = 1mA l 1 5 mV IN LOAD Load Regulation LT1763-1.5 V = 2.5V, ∆I = 1mA to 500mA 3 8 mV IN LOAD V = 2.5V, ∆I = 1mA to 500mA l 15 mV IN LOAD LT1763-1.8 V = 2.8V, ∆I = 1mA to 500mA 4 9 mV IN LOAD V = 2.8V, ∆I = 1mA to 500mA l 18 mV IN LOAD LT1763-2.5 V = 3.5V, ∆I = 1mA to 500mA 5 12 mV IN LOAD V = 3.5V, ∆I = 1mA to 500mA l 25 mV IN LOAD LT1763-3 V = 4V, ∆I = 1mA to 500mA 7 15 mV IN LOAD V = 4V, ∆I = 1mA to 500mA l 30 mV IN LOAD LT1763-3.3 V = 4.3V, ∆I = 1mA to 500mA 7 17 mV IN LOAD V = 4.3V, ∆I = 1mA to 500mA l 33 mV IN LOAD LT1763-5 V = 6V, ∆I = 1mA to 500mA 12 25 mV IN LOAD V = 6V, ∆I = 1mA to 500mA l 50 mV IN LOAD LT1763 (Note 3) V = 2.3V, ∆I = 1mA to 500mA 2 6 mV IN LOAD C, I Grade: V = 2.3V, ∆I = 1mA to 500mA l 12 mV IN LOAD MP Grade: V = 2.35V, ∆I = 1mA to 500mA l 12 mV IN LOAD Dropout Voltage I = 10mA 0.13 0.19 V LOAD V = V I = 10mA l 0.25 V IN OUT(NOMINAL) LOAD (Notes 5, 6, 11) I = 50mA 0.17 0.22 V LOAD I = 50mA l 0.32 V LOAD I = 100mA 0.20 0.24 V LOAD I = 100mA l 0.34 V LOAD I = 500mA 0.30 0.35 V LOAD I = 500mA l 0.45 V LOAD 1763fh 4 For more information www.linear.com/LT1763

LT1763 Series elecTrical characTerisTics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25°C. (Note 2) A PARAMETER CONDITIONS MIN TYP MAX UNITS GND Pin Current I = 0mA l 30 75 µA LOAD V = V I = 1mA l 65 120 µA IN OUT(NOMINAL) LOAD (Notes 5, 7) I = 50mA l 1.1 1.6 mA LOAD I = 100mA l 2 3 mA LOAD I = 250mA l 5 8 mA LOAD I = 500mA l 11 16 mA LOAD Output Voltage Noise C = 10µF, C = 0.01µF, I = 500mA, BW = 10Hz to 100kHz 20 µV OUT BYP LOAD RMS ADJ Pin Bias Current (Notes 3, 8) 30 100 nA Shutdown Threshold V = Off to On l 0.8 2 V OUT V = On to Off l 0.25 0.65 V OUT SHDN Pin Current V = 0V 0.1 µA SHDN (Note 9) V = 20V 1 µA SHDN Quiescent Current in Shutdown V = 6V, V = 0V 0.1 1 µA IN SHDN Ripple Rejection V – V = 1.5V (Avg), V = 0.5V , f = 120Hz, 50 65 dB IN OUT RIPPLE P-P RIPPLE I = 500mA LOAD Current Limit V = 7V, V = 0V IN OUT C, I Grade: V = V + 1V or 2.3V (Note 12), ∆V = –0.1V l 520 mA IN OUT(NOMINAL) OUT MP Grade: V = 2.35V (Note 12), ∆V = –0.1V l 520 mA IN OUT Input Reverse Leakage Current V = –20V, V = 0V l 1 mA IN OUT Reverse Output Current LT1763-1.5 V = 1.5V, V < 1.5V 10 20 µA OUT IN (Note 10) LT1763-1.8 V = 1.8V, V < 1.8V 10 20 µA OUT IN LT1763-2.5 V = 2.5V, V < 2.5V 10 20 µA OUT IN LT1763-3 V = 3V, V < 3V 10 20 µA OUT IN LT1763-3.3 V = 3.3V, V < 3.3V 10 20 µA OUT IN LT1763-5 V = 5V, V < 5V 10 20 µA OUT IN LT1763 (Note 3) V = 1.22V, V < 1.22V 5 10 µA OUT IN Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 6: Dropout voltage is the minimum input to output voltage differential may cause permanent damage to the device. Exposure to any Absolute needed to maintain regulation at a specified output current. In dropout, the Maximum Rating condition for extended periods may affect device output voltage will be equal to: V – V . IN DROPOUT reliability and lifetime. Note 7: GND pin current is tested with V = V or V = 2.3V IN OUT(NOMINAL) IN Note 2: The LT1763 regulators are tested and specified under pulse (C, I grade) or 2.35V (MP grade), whichever is greater, and a current load conditions such that TJ @ TA. The LT1763 (C grade) is 100% tested source load. This means the device is tested while operating in its dropout at T = 25°C; performance at –40°C and 125°C is assured by design, region. This is the worst-case GND pin current. The GND pin current will A characterization and correlation with statistical process controls. The decrease slightly at higher input voltages. LT1763 (I grade) is guaranteed over the full –40°C to 125°C operating Note 8: ADJ pin bias current flows into the ADJ pin. junction temperature range. The LT1763 (MP grade) is 100% tested and Note 9: SHDN pin current flows into the SHDN pin. guaranteed over the –55°C to 125°C operating junction temperature range. Note 10: Reverse output current is tested with the IN pin grounded and the Note 3: The LT1763 (adjustable version) is tested and specified for these OUT pin forced to the rated output voltage. This current flows into the OUT conditions with the ADJ pin connected to the OUT pin. pin and out the GND pin. Note 4: Operating conditions are limited by maximum junction Note 11: For the LT1763, LT1763-1.5 and LT1763-1.8 dropout voltage will temperature. The regulated output voltage specification will not apply be limited by the minimum input voltage specification under some output for all possible combinations of input voltage and output current. When voltage/load conditions. See the curve of Minimum Input Voltage in the operating at maximum input voltage, the output current range must be Typical Performance Characteristics. limited. When operating at maximum output current, the input voltage Note 12: To satisfy requirements for minimum input voltage, current limit range must be limited. is tested at V = V + 1V or 2.3V (C, I grade) or 2.35V IN OUT(NOMINAL) Note 5: To satisfy requirements for minimum input voltage, the LT1763 (MP grade), whichever is greater. (adjustable version) is tested and specified for these conditions with an external resistor divider (two 250k resistors) for an output voltage of 2.44V. The external resistor divider will add a 5µA DC load on the output. 1763fh 5 For more information www.linear.com/LT1763

LT1763 Series Typical perForMance characTerisTics Typical Dropout Voltage Guaranteed Dropout Voltage Dropout Voltage 500 500 500 = TEST POINTS 450 V) 450 450 V) 400 TJ = 125°C AGE (m 400 V)400 IL = 250mA IL = 500mA AGE (m 335000 T VOLT 335000 TJ ≤ 125°C AGE (m335000 IL = 100mA T U T UT VOL 225000 TJ = 25°C DROPO 225000 TJ ≤ 25°C UT VOL225000 ROPO 150 TEED 150 ROPO150 D N D 100 A 100 100 AR IL = 1mA 50 GU 50 50 IL = 50mA IL = 10mA 0 0 0 0 50 100150200 250300350 400450 500 0 50 100150200 250300350 400450 500 –50 –25 0 25 50 75 100 125 OUTPUT CURRENT (mA) OUTPUT CURRENT (mA) TEMPERATURE (°C) 1763 G01 1763 G02 1763 G03 LT1763-1.5 LT1763-1.8 Quiescent Current Output Voltage Output Voltage 50 1.528 1.84 IL = 1mA IL = 1mA 45 1.521 1.83 40 A) 1.514 1.82 RENT (µ 3350 VSHDN = VIN AGE (V)1.507 AGE (V) 1.81 R T T UIESCENT CU 221505 OUTPUT VOL111...544098036 OUTPUT VOL 111...877098 Q 10 VIN = 6V 5 RL = ∞, IL = 0 (LT1763-1.5/-1.8/-2.5/-3/-3.3/-5) 1.479 1.77 RL = 250k, IL = 5µA (LT1763) 0 1.472 1.76 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 1763 G04 1763 G05 1763 G06 LT1763-2.5 LT1763-3 LT1763-3.3 Output Voltage Output Voltage Output Voltage 2.54 3.060 3.360 IL = 1mA IL = 1mA IL = 1mA 2.53 3.045 3.345 2.52 3.030 3.330 V) V) V) GE (2.51 GE ( 3.015 GE ( 3.315 A A A T T T L L L O2.50 O 3.000 O 3.300 V V V T T T PU2.49 PU 2.985 PU 3.285 T T T U U U O O O 2.48 2.970 3.270 2.47 2.955 3.255 2.46 2.940 3.240 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 1763 G07 1763 G08 1763 G09 1763fh 6 For more information www.linear.com/LT1763

2 LT1763 Series Typical perForMance characTerisTics LT1763-5 LT1763 LT1763-1.5 Output Voltage ADJ Pin Voltage Quiescent Current 5.100 1.240 250 IL = 1mA IL = 1mA 225 TJ = 25°C 5.075 1.235 RL = ∞ 200 5.050 1.230 A) AGE (V) 5.025 AGE (V) 1.225 RENT (µ 117550 OUTPUT VOLT 544...099075050 ADJ PIN VOLT 111...222211050 UIESCENT CUR 11207505 Q 50 VSHDN = VIN 4.925 1.205 25 VSHDN = 0V 4.900 1.200 0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 0 1 2 3 4 5 6 7 8 9 10 TEMPERATURE (°C) TEMPERATURE (°C) INPUT VOLTAGE (V) 1763 G10 1763 G11 1763 G12 SHDN SHDN LT1763-1.8 LT1763-2.5 LT1763-3 Quiescent Current Quiescent Current Quiescent Current 250 250 250 225 TJ = 25°C 225 TJ = 25°C 225 TJ = 25°C RL = ∞ RL = ∞ RL = ∞ 200 200 200 A) A) A) µ µ µ T ( 175 T ( 175 T ( 175 N N N RE 150 RE 150 RE 150 R R R CU 125 CU 125 CU 125 T T T EN 100 EN 100 EN 100 C C C S S S E 75 E 75 E 75 UI UI UI Q 50 VSHDN = VIN Q 50 VSHDN = VIN Q 50 VSHDN = VIN 25 25 25 VSHDN = 0V VSHDN = 0V VSHDN = 0V 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1763 G13 1763 G14 1763 G15 LT1763-3.3 LT1763-5 LT1763 Quiescent Current Quiescent Current Quiescent Current 250 250 40 225 TJ = 25°C 225 TJ = 25°C TJ = 25°C RL = ∞ RL = ∞ 35 RL = 250k A) 200 A) 200 A) 30 VSHDN = VIN µ µ µ T ( 175 T ( 175 T ( REN 150 REN 150 REN 25 R R R CU 125 CU 125 CU 20 T T T CEN 100 CEN 100 CEN 15 S S S E 75 E 75 E UI UI UI 10 Q Q Q 50 50 VSHDN = VIN VSHDN = VIN 5 25 25 VSHDN = 0V VSHDN = 0V VSHDN = 0V 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 2 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1763 G16 1763 G17 1763 G18 1763fh 7 For more information www.linear.com/LT1763

LT1763 Series Typical perForMance characTerisTics LT1763-1.5 LT1763-1.8 LT1763-2.5 GND Pin Current GND Pin Current GND Pin Current 1200 1200 1200 1000 1000 1000 RL = 50Ω ENT (µA) 800 IRLL = = 5 300mΩA* TJ = 25°C ENT (µA) 800 IRLL = = 5 306mΩA* TJ = 25°C ENT (µA) 800 IL = 50mA* TJ = 25°C URR 600 V*FINO =R VVSOHUDTN = 1.5V URR 600 V*FINO =R VVSOHUDTN = 1.8V URR 600 V*FINO =R VVSOHUDTN = 2.5V C C C N N N D PI 400 RL = 150Ω D PI 400 RL = 180Ω D PI 400 RL = 250Ω GN IL = 10mA* GN IL = 10mA* GN IL = 10mA* 200 RL = 1.5k 200 RL = 1.8k 200 RL = 2.5k IL = 1mA* IL = 1mA* IL = 1mA* 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1763 G19 1763 G20 1763 G21 LT1763-3 LT1763-3.3 LT1763-5 GND Pin Current GND Pin Current GND Pin Current 1200 1200 1200 1000 1000 1000 µA) IRLL = = 5 600mΩA* µA) IRLL = = 5 606mΩA* µA) IRLL = = 5 100m0AΩ* ENT ( 800 TJ = 25°C ENT ( 800 TJ = 25°C ENT ( 800 TJ = 25°C URR 600 V*FINO =R VVSOHUDTN = 3V URR 600 V*FINO =R VVSOHUDTN = 3.3V URR 600 V*FINO =R VVSOHUDTN = 5V C C C N N N GND PI 400 IRLL = = 1 300m0AΩ* GND PI 400 IRLL = = 1 303m0AΩ* GND PI 400 IRLL = = 1 500m0AΩ* 200 RL = 3k 200 RL = 3.3k 200 RL = 5k IL = 1mA* IL = 1mA* IL = 1mA* 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1763 G22 1763 G23 1763 G24 LT1763 LT1763-1.5 LT1763-1.8 GND Pin Current GND Pin Current GND Pin Current 1200 12 12 TJ = 25°C TJ = 25°C VIN = VSHDN VIN = VSHDN 1000 RL = 24.4Ω 10 *FOR VOUT = 1.5V 10 *FOR VOUT = 1.8V N CURRENT (µA) 860000 IL = 50mA* VT*FJIN O= =R 2 VV5SO°HCUDTN = 1.22V N CURRENT (mA) 86 IL R= L5 =0 03mΩA* IRLL = = 3 50Ω0mA* N CURRENT (mA) 86 ILR =L 5=0 30.m6ΩA* IRLL = = 3 60Ω0mA* D PI 400 RL = 122Ω D PI 4 D PI 4 GN IL = 10mA* GN RL = 15Ω GN RL = 18Ω 200 RL = 1.22k 2 IL = 100mA* 2 IL = 100mA* IL = 1mA* 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1763 G25 1763 G26 1763 G27 1763fh 8 For more information www.linear.com/LT1763

LT1763 Series Typical perForMance characTerisTics LT1763-2.5 LT1763-3 LT1763-3.3 GND Pin Current GND Pin Current GND Pin Current 12 12 12 TJ = 25°C TJ = 25°C TJ = 25°C VIN = VSHDN VIN = VSHDN VIN = VSHDN 10 *FOR VOUT = 2.5V 10 *FOR VOUT = 3V 10 *FOR VOUT = 3.3V A) A) A) NT (m 8 IL R= L5 =0 05mΩA* NT (m 8 IL R= L5 =0 06mΩA* NT (m 8 ILR =L 5=0 60.m6ΩA* E E E R R R N CUR 6 IRLL = = 3 80.03m3ΩA* N CUR 6 ILR =L 3=0 100mΩA* N CUR 6 ILR =L 3=0 101mΩA* PI PI PI D 4 D 4 D 4 N N N G RL = 25Ω G RL = 30Ω G RL = 33Ω 2 IL = 100mA* 2 IL = 100mA* 2 IL = 100mA* 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (V) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1763 G28 1763 G29 1763 G30 LT1763-5 LT1763 GND Pin Current GND Pin Current GND Pin Current vs I LOAD 12 12 12 TJ = 25°C TJ = 25°C VIN = VOUT(NOMINAL) + 1V 10 V*FINO =R VVSOHUDTN = 5V ILR =L 5=0 100mΩA* 10 V*FINO =R VVSOHUDTN = 1.22V 10 A) A) RL = 2.44Ω A) T (m 8 T (m 8 IL = 500mA* T (m 8 N N N E E E CURR 6 IRL L= =3 0106m.7AΩ* CURR 6 IRLL = = 3 40.00m7ΩA* CURR 6 N N N PI PI PI D 4 D 4 D 4 N N N G RL = 50Ω G RL = 12.2Ω G 2 IL = 100mA* 2 IL = 100mA* 2 0 0 0 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 50 100150200 250300350 400450 500 INPUT VOLTAGE (V) INPUT VOLTAGE (V) OUTPUT CURRENT (mA) 1763 G31 1763 G32 1763 G33 SHDN Pin Threshold SHDN Pin Threshold (On-to-Off) (Off-to-On) SHDN Pin Input Current 1.0 1.0 1.4 IL = 1mA 0.9 0.9 1.2 D (V) 00..87 D (V) 00..87 IL = 500mA NT (µA) 1.0 OL OL RE H 0.6 H 0.6 R S S U 0.8 E E C N THR 00..54 N THR 00..54 IL = 1mA NPUT 0.6 HDN PI 0.3 HDN PI 0.3 N PIN I 0.4 S 0.2 S 0.2 HD S 0.2 0.1 0.1 0 0 0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 0 1 2 3 4 5 6 7 8 9 10 TEMPERATURE (°C) TEMPERATURE (°C) SHDN PIN VOLTAGE (V) 1763 G34 1763 G35 1763 G36 1763fh 9 For more information www.linear.com/LT1763

LT1763 Series Typical perForMance characTerisTics SHDN Pin Input Current ADJ Pin Bias Current Current Limit 1.6 140 1.0 VSHDN = 20V 0.9 VOUT = 0V URRENT (µA) 111...420 RRENT (nA)11208000 MIT (A) 000...876 DN PIN INPUT C 000...864 DJ PIN BIAS CU 6400 CURRENT LI 000...543 H A 0.2 S 0.2 20 0.1 0 0 0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 0 1 2 3 4 5 6 7 TEMPERATURE (°C) TEMPERATURE (°C) INPUT VOLTAGE (V) 1763 G37 1763 G38 1763 G39 Current Limit Reverse Output Current Reverse Output Current 1.2 100 20 VVIONU =T =7 0V 90 CTJU =R R25E°NCT, FVLINO W= 0SV LT1763-1.5 18 VVIONU =T =0 V1,. 5VVO U(LT T=1 17.6232-V1 .(5L)T1763) MIT (A) 10..08 CURRENT (µA) 876000 IVNOTUOTL OT=1 UV7TA6PD3UJ- 1T(L. 8PTLI1NT716736)3 CURRENT (µA) 111642 VVVVVOOOOOUUUUUTTTTT ===== 12335..V.V853 VVV((LL (((TTLLL11TTT771116677733666--33335---))123...853))) T LI 0.6 UT 50 LT1763-2.5 UT 10 N P P RE UT 40 LT1763-3 UT 8 LT1763-1.5/-1.8/ R O O CU 0.4 SE 30 LT1763-3.3 SE 6 -2.5/-3/-3.3/-5 R R E E 0.2 REV 20 REV 4 LT1763 10 LT1763-5 2 0 0 0 –50 –25 0 25 50 75 100 125 0 1 2 3 4 5 6 7 8 9 10 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) OUTPUT VOLTAGE (V) TEMPERATURE (°C) 1763 G40 1763 G41 1763 G42 Input Ripple Rejection Input Ripple Rejection Ripple Rejection 80 80 68 70 70 CBYP = 0.01µF 66 B) 60 B) 60 B) 64 d d d ON ( 50 COUT = 10µF ON ( 50 CBYP = 1000pF ON ( 62 CTI CTI CBYP = 100pF CTI E 40 E 40 E 60 EJ EJ EJ R R R LE 30 LE 30 LE 58 P P P P P P RI 20 IL = 500mA RI 20 IL = 500mA RI 56 VIN = VOUT (NOMINAL) + VIN = VOUT(NOMINAL) + COUT = 4.7µF VIN = VOUT(NOMINAL) + 1V + 0.5VP-P RIPPLE 10 1V + 50mVRMS RIPPLE 10 1V + 50mVRMS RIPPLE 54 AT f = 120Hz CBYP = 0 COUT = 10µF IL = 500mA 0 0 52 10 100 1k 10k 100k 1M 10 100 1k 10k 100k 1M –50 –25 0 25 50 75 100 125 FREQUENCY (Hz) FREQUENCY (Hz) TEMPERATURE (°C) 1763 G43 1763 G44 1763 G45 1763fh 10 For more information www.linear.com/LT1763

LT1763 Series Typical perForMance characTerisTics LT1763 Output Noise Spectral Density Minimum Input Voltage Load Regulation C = 0 BYP 2.50 5 LT1763-1.5 Hz) 10 M INPUT VOLTAGE (V)221111......207520505050 ILI L= =5 010mmAA REGULATION (mV) ––1050 LLTT11776633-L3T17L6T31-37.633-2.5 LT1763-1.8 SPECTRAL DENSITY (µV/√ 1 LLTT11776633-L5T17L6T31-73L6T31-726.53-3.3 U D –15 LT1763-5 E 0.1 LT1763-1.8 LT1763-1.5 M0.75 A S MINI00..5205 VOUT = 1.22V LO –20 V∆IINL == V1mOUAT (TNOO M50IN0AmL)A + 1V UTPUT NOI ICLO =U T5 0=0 1m0AµF O 0 –25 0.01 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 10 100 1k 10k 100k TEMPERATURE (°C) TEMPERATURE (°C) FREQUENCY (Hz) 1763 G46 1763 G47 1763 G48 RMS Output Noise RMS Output Noise Output Noise Spectral Density vs Bypass Capacitor vs Load Current (10Hz to 100kHz) Hz)√ 10 COUT = 10µF 160 COUT = 10µF 160 COUT = 10µF ECTRAL DENSITY (µV/ 1 LILTLT1 =17 75606303m-5A CBCYBPY P= =1 010000ppFF NOISE (µV)RMS11142080000 LT1763-5 LT176L3T-31.736L3T-fI L31= 7= 16 5030H-02zm. 5TAO 100kHz NOISE (µV)RMS11142080000 CCBBYYPP == 00.01µF LT1763-5 NOISE SP 0.1 CBYP = 0.01µF OUTPUT 6400 LT1763 OUTPUT 6400 LT1763 T U LT1763-5 TP 20 LT1763-1.8 20 OU LT1763-1.5 LT1763 0.01 0 0 10 100 1k 10k 100k 10 100 1000 10000 0.01 0.1 1 10 100 1000 FREQUENCY (Hz) CBYP (pF) LOAD CURRENT (mA) 1763 G49 1763 G50 1763 G51 LT1763-5 LT1763-5 LT1763-5 10Hz to 100kHz Output Noise 10Hz to 100kHz Output Noise 10Hz to 100kHz Output Noise CBYP = 0 CBYP = 100pF CBYP = 1000pF VOUT VOUT 100µV/DIV 100µV/DIV VOUT 100µV/DIV 1ms/DIV 1763 G52 1ms/DIV 1763 G53 1ms/DIV 1763 G54 COUT = 10µF COUT = 10µF COUT = 10µF IL = 500mA IL = 500mA IL = 500mA 1763fh 11 For more information www.linear.com/LT1763

LT1763 Series Typical perForMance characTerisTics LT1763-5 LT1763-5 LT1763-5 10Hz to 100kHz Output Noise Transient Response Transient Response CBYP = 0.01µF CBYP = 0 CBYP = 0.01µF 0.4 VIN = 6V 0.10 VIN = 6V 100µVV/ODUIVT UTPUT VOLTAGEDEVIATION (V)–00..202 CCIONU =T =1 01µ0FµF UTPUT VOLTAGEDEVIATION (V)–00..00505 CCIONU =T =1 01µ0FµF O –0.4 O –0.10 T T EN 600 EN 600 R R COUT = 10µF 1ms/DIV 1763 G55 OAD CUR(mA)420000 OAD CUR(mA) 420000 IL = 500mA L 0 L 0 0 200 400 600 800 1000 0 10 20 30 40 50 60 70 80 90 100 TIME (µs) TIME (µs) 1763 G56 1763 G57 1763fh 12 For more information www.linear.com/LT1763

LT1763 Series pin FuncTions (DE12/S8) NC (Pins 1, 4, 9, 12) DE12 Only: No Connect. No connect BYP (Pin 6/Pin 4): Bypass. The BYP pin is used to bypass pins have no connection to any internal circuitry. These the reference of the LT1763 regulators to achieve low noise pins may be tied to either GND or V , or left floating. performance from the regulator. The BYP pin is clamped IN internally to ±0.6V (one V ). A small capacitor from the OUT (Pins 2, 3/Pin 1): Output. The output supplies power BE output to this pin will bypass the reference to lower the to the load. A minimum output capacitor of 3.3µF is re- output voltage noise. A maximum value of 0.01µF can quired to prevent oscillations. Larger output capacitors be used for reducing output voltage noise to a typical will be required for applications with large transient loads 20µV over a 10Hz to 100kHz bandwidth. If not used, to limit peak voltage transients. See the Applications Infor- RMS this pin must be left unconnected. mation section for more information on output capacitance and reverse output characteristics. GND (Pins 7, Exposed Pad Pin 13/Pins 3, 6, 7): Ground. The exposed pad of the DFN package is an electrical con- ADJ (Pin 5/Pin 2): Adjust. For the adjustable LT1763, this nection to GND. To ensure proper electrical and thermal is the input to the error amplifier. This pin is internally performance, solder Pin 13 to the PCB ground and tie clamped to ±7V. It has a bias current of 30nA which flows directly to Pin 7. Connect the bottom of the output volt- into the pin (see the curve of ADJ Pin Bias Current vs age setting resistor divider directly to the GND pins for Temperature in the Typical Performance Characteristics optimum load regulation performance. section). The ADJ pin voltage is 1.22V referenced to ground and the output voltage range is 1.22V to 20V. SHDN (Pin 8/Pin 5): Shutdown. The SHDN pin is used to put the LT1763 regulators into a low power shutdown SENSE (Pin 5/Pin 2): Output Sense. For fixed volt- state. The output will be off when the SHDN pin is pulled age versions of the LT1763 (LT1763-1.5/LT1763-1.8/ low. The SHDN pin can be driven either by 5V logic or LT1763-2.5/LT1763-3/LT1763-3.3/LT1763-5), the SENSE open-collector logic with a pull-up resistor. The pull-up pin is the input to the error amplifier. Optimum regula- resistor is required to supply the pull-up current of the tion will be obtained at the point where the SENSE pin open-collector gate, normally several microamperes, and is connected to the OUT pin of the regulator. In critical the SHDN pin current, typically 1µA. If unused, the SHDN applications, small voltage drops are caused by the re- sistance (RP) of PC traces between the regulator and the pin must be connected to VIN. The device will be in the low load. These may be eliminated by connecting the SENSE power shutdown state if the SHDN pin is not connected. pin to the output at the load as shown in Figure 1 (Kelvin IN (Pin 10, 11/Pin 8): Input. Power is supplied to the device Sense Connection). through the IN pin. A bypass capacitor is required on this pin if the device is more than six inches away from the 8 1 RP IN OUT main input filter capacitor. In general, the output imped- ance of a battery rises with frequency, so it is advisable to LT1763 + 5 2 + include a bypass capacitor in battery-powered circuits. A VIN SHDN SENSE LOAD bypass capacitor in the range of 1µF to 10µF is sufficient. GND 3 The LT1763 regulators are designed to withstand reverse RP voltages on the IN pin with respect to ground and the OUT 1763 F01 pin. In the case of a reverse input, which can happen if Figure 1. Kelvin Sense Connection a battery is plugged in backwards, the device will act as if there is a diode in series with its input. There will be Note that the voltage drop across the external PC traces will no reverse current flow into the regulator and no reverse add to the dropout voltage of the regulator. The SENSE pin voltage will appear at the load. The device will protect both bias current is 10µA at the nominal rated output voltage. The itself and the load. SENSE pin can be pulled below ground (as in a dual supply system where the regulator load is returned to a negative supply) and still allow the device to start and operate. 1763fh 13 For more information www.linear.com/LT1763

LT1763 Series applicaTions inForMaTion The LT1763 series are 500mA low dropout regulators with to 1.22V: V /1.22V. For example, load regulation for an OUT micropower quiescent current and shutdown. The devices output current change of 1mA to 500mA is –2mV typical are capable of supplying 500mA at a dropout voltage of at V = 1.22V. At V = 12V, load regulation is: OUT OUT 300mV. Output voltage noise can be lowered to 20µV RMS (12V/1.22V)(–2mV) = –19.6mV over a 10Hz to 100kHz bandwidth with the addition of a 0.01µF reference bypass capacitor. Additionally, the reference bypass capacitor will improve transient response of the regulator, lowering the settling time for transient load IN OUT VOUT + conditions. The low operating quiescent current (30µA) VIN LT1763 R2 drops to less than 1µA in shutdown. In addition to the ADJ VOUT=1.22V1+RR21+(IADJ)(R2) GND low quiescent current, the LT1763 regulators incorporate R1 VADJ=1.22V several protection features which make them ideal for use IADJ=30nA AT 25°C OUTPUT RANGE = 1.22V TO 20V in battery-powered systems. The devices are protected 1763 F02 against both reverse input and reverse output voltages. In battery backup applications where the output can be Figure 2. Adjustable Operation held up by a backup battery when the input is pulled to ground, the LT1763-X acts like it has a diode in series with Bypass Capacitance and Low Noise Performance its output and prevents reverse current flow. Additionally, in dual supply applications where the regulator load is The LT1763 regulators may be used with the addition of returned to a negative supply, the output can be pulled a bypass capacitor from V to the BYP pin to lower OUT below ground by as much as 20V and still allow the device output voltage noise. A good quality low leakage capacitor to start and operate. is recommended. This capacitor will bypass the reference of the regulator, providing a low frequency noise pole. Adjustable Operation The noise pole provided by this bypass capacitor will The adjustable version of the LT1763 has an output voltage lower the output voltage noise to as low as 20µVRMS range of 1.22V to 20V. The output voltage is set by the with the addition of a 0.01µF bypass capacitor. Using ratio of two external resistors, as shown in Figure 2. The a bypass capacitor has the added benefit of improving device servos the output to maintain the ADJ pin voltage transient response. With no bypass capacitor and a 10µF at 1.22V referenced to ground. The current in R1 is then output capacitor, a 10mA to 500mA load step will settle equal to 1.22V/R1 and the current in R2 is the current to within 1% of its final value in less than 100µs. With in R1 plus the ADJ pin bias current. The ADJ pin bias the addition of a 0.01µF bypass capacitor, the output will current, 30nA at 25°C, flows through R2 into the ADJ pin. settle to within 1% for a 10mA to 500mA load step in less The output voltage can be calculated using the formula in than 10µs, with total output voltage deviation of less than Figure 2. The value of R1 should be no greater than 250k 2.5% (see the LT1763-5 Transient Response curve in the to minimize errors in the output voltage caused by the Typical Performance Characteristics section). However, ADJ pin bias current. Note that in shutdown the output regulator start-up time is proportional to the size of the is turned off and the divider current will be zero. Curves bypass capacitor, slowing to 15ms with a 0.01µF bypass of ADJ Pin Voltage vs Temperature and ADJ Pin Bias capacitor and 10µF output capacitor. Current vs Temperature appear in the Typical Performance Characteristics section. The adjustable device is tested and specified with the ADJ pin tied to the OUT pin for an output voltage of 1.22V. Specifications for output voltages greater than 1.22V will be proportional to the ratio of the desired output voltage 1763fh 14 For more information www.linear.com/LT1763

LT1763 Series applicaTions inForMaTion Output Capacitance and Transient Response 4.0 3.5 The LT1763 regulators are designed to be stable with a wide range of output capacitors. The ESR of the output 3.0 STABLE REGION capacitor affects stability, most notably with small capaci- 2.5 Ω) tors. A minimum output capacitor of 3.3µF with an ESR R ( 2.0 S of 3Ω, or less, is recommended to prevent oscillations. E 1.5 CBYP = 0 The LT1763-X is a micropower device and output transient CBYP = 100pF 1.0 CBYP = 330pF response will be a function of output capacitance. Larger CBYP ≥ 1000pF 0.5 values of output capacitance decrease the peak deviations and provide improved transient response for larger load 0 1 2 3 4 5 6 7 8 910 current changes. Bypass capacitors, used to decouple OUTPUT CAPACITANCE (µF) 1763 F03 individual components powered by the LT1763-X, will Figure 3. Stability increase the effective output capacitor value. With larger capacitors used to bypass the reference (for low noise operation), larger values of output capacitors are needed. 20 For 100pF of bypass capacitance, 4.7µF of output capaci- BOTH CAPACITORS ARE 16V, 1210 CASE SIZE, 10µF tor is recommended. With a 1000pF bypass capacitor or 0 larger, a 6.8µF output capacitor is recommended. %) X5R E (–20 U The shaded region of Figure 3 defines the range over AL V which the LT1763 regulators are stable. The minimum ESR E IN –40 G needed is defined by the amount of bypass capacitance N A–60 H used, while the maximum ESR is 3Ω. C Y5V –80 Extra consideration must be given to the use of ceramic capacitors. Ceramic capacitors are manufactured with a –100 0 2 4 6 8 10 12 14 16 variety of dielectrics, each with different behavior across DC BIAS VOLTAGE (V) 1763 F04 temperature and applied voltage. The most common Figure 4. Ceramic Capacitor DC Bias Characteristics dielectrics used are specified with EIA temperature characteristic codes of Z5U, Y5V, X5R and X7R. The Z5U and Y5V dielectrics are good for providing high capacitances 40 in a small package, but they tend to have strong voltage and temperature coefficients, as shown in Figures 4 20 and 5. When used with a 5V regulator, a 16V 10µF Y5V %) 0 X5R capacitor can exhibit an effective value as low as 1µF to E ( U L –20 2µF for the DC bias voltage applied and over the operating VA N temperature range. The X5R and X7R dielectrics result in E I –40 G Y5V N more stable characteristics and are more suitable for use A H –60 C as the output capacitor. The X7R type has better stability –80 BOTH CAPACITORS ARE 16V, across temperature, while the X5R is less expensive and is 1210 CASE SIZE, 10µF available in higher values. Care still must be exercised when –100 –50 –25 0 25 50 75 100 125 using X5R and X7R capacitors; the X5R and X7R codes TEMPERATURE (°C) 1763 F05 only specify operating temperature range and maximum Figure 5. Ceramic Capacitor Temperature Characteristics capacitance change over temperature. Capacitance change due to DC bias with X5R and X7R capacitors is better than 1763fh 15 For more information www.linear.com/LT1763

LT1763 Series applicaTions inForMaTion Y5V and Z5U capacitors, but can still be significant enough Thermal Considerations to drop capacitor values below appropriate levels. Capacitor The power handling capability of the device will be limited DC bias characteristics tend to improve as component by the maximum rated junction temperature (125°C). The case size increases, but expected capacitance at operating power dissipated by the device will be made up of two voltage should be verified. components: Voltage and temperature coefficients are not the only 1. Output current multiplied by the input/output voltage sources of problems. Some ceramic capacitors have a differential: (I )(V – V ), and OUT IN OUT piezoelectric response. A piezoelectric device generates voltage across its terminals due to mechanical stress, 2. GND pin current multiplied by the input voltage: similar to the way a piezoelectric accelerometer or (IGND)(VIN). microphone works. For a ceramic capacitor, the stress The GND pin current can be found by examining the GND can be induced by vibrations in the system or thermal Pin Current curves in the Typical Performance Character- transients. The resulting voltages produced can cause istics section. Power dissipation will be equal to the sum appreciable amounts of noise, especially when a ceramic of the two components listed above. capacitor is used for noise bypassing. A ceramic capacitor The LT1763 series regulators have internal thermal limiting produced Figure 6’s trace in response to light tapping from a designed to protect the device during overload conditions. pencil. Similar vibration induced behavior can masquerade For continuous normal conditions, the maximum junction as increased output voltage noise. temperature rating of 125°C must not be exceeded. It is important to give careful consideration to all sources of LT1763-5 thermal resistance from junction-to-ambient. Additional COUT = 10µF CBYP = 0.01µF heat sources mounted nearby must also be considered. ILOAD = 100mA For surface mount devices, heat sinking is accomplished VOUT 500µV/DIV by using the heat spreading capabilities of the PC board and its copper traces. Copper board stiffeners and plated through-holes can also be used to spread the heat gener- ated by power devices. 1763 F06 100ms/DIV The following tables list thermal resistance for several different board sizes and copper areas. All measurements Figure 6. Noise Resulting from Tapping on a Ceramic Capacitor were taken in still air on 3/32" FR-4 board with one ounce copper. Table 1. DE Package, 12-Lead DFN COPPER AREA THERMAL RESISTANCE TOPSIDE* BACKSIDE BOARD AREA (JUNCTION-TO-AMBIENT) 2500mm2 2500mm2 2500mm2 40°C/W 1000mm2 2500mm2 2500mm2 45°C/W 225mm2 2500mm2 2500mm2 50°C/W 100mm2 2500mm2 2500mm2 60°C/W * Device is mounted on topside 1763fh 16 For more information www.linear.com/LT1763

LT1763 Series applicaTions inForMaTion Protection Features Table 2. SO-8 Package, 8-Lead SO COPPER AREA The LT1763 regulators incorporate several protection THERMAL RESISTANCE features which make them ideal for use in battery-powered TOPSIDE* BACKSIDE BOARD AREA (JUNCTION-TO-AMBIENT) circuits. In addition to the normal protection features 2500mm2 2500mm2 2500mm2 60°C/W associated with monolithic regulators, such as current 1000mm2 2500mm2 2500mm2 60°C/W limiting and thermal limiting, the devices are protected 225mm2 2500mm2 2500mm2 68°C/W against reverse input voltages, reverse output voltages 100mm2 2500mm2 2500mm2 74°C/W and reverse voltages from output to input. 50mm2 2500mm2 2500mm2 86°C/W Current limit protection and thermal overload protection * Device is mounted on topside are intended to protect the device against current overload conditions at the output of the device. For normal operation, Calculating Junction Temperature the junction temperature should not exceed 125°C. Example: Given an output voltage of 3.3V, an input voltage The input of the device will withstand reverse voltages of range of 4V to 6V, an output current range of 0mA to 250mA 20V. Current flow into the device will be limited to less and a maximum ambient temperature of 50°C, what will than 1mA (typically less than 100µA) and no negative the maximum junction temperature be? voltage will appear at the output. The device will protect both itself and the load. This provides protection against The power dissipated by the device will be equal to: batteries which can be plugged in backward. I (V – V ) + I (V ) OUT(MAX) IN(MAX) OUT GND IN(MAX) The output of the LT1763-X can be pulled below ground where, without damaging the device. If the input is left open-circuit or grounded, the output can be pulled below ground by I = 250mA OUT(MAX) 20V. For fixed voltage versions, the output will act like a V = 6V IN(MAX) large resistor, typically 500k or higher, limiting current flow I at (I = 250mA, V = 6V) = 5mA GND OUT IN to less than 100µA. For adjustable versions, the output So, will act like an open circuit; no current will flow out of the P = 250mA(6V – 3.3V) + 5mA(6V) = 0.71W pin. If the input is powered by a voltage source, the output will source the short-circuit current of the device and will The thermal resistance will be in the range of 60°C/W to protect itself by thermal limiting. In this case, grounding 86°C/W, depending on the copper area. So, the junction the SHDN pin will turn off the device and stop the output temperature rise above ambient will be approximately from sourcing the short-circuit current. equal to: The ADJ pin of the adjustable device can be pulled above 0.71W(75°C/W) = 53.3°C or below ground by as much as 7V without damaging the The maximum junction temperature will then be equal to device. If the input is left open-circuit or grounded, the the maximum junction temperature rise above ambient ADJ pin will act like an open circuit when pulled below plus the maximum ambient temperature, or: ground and like a large resistor (typically 100k) in series T = 50°C + 53.3°C = 103.3°C with a diode when pulled above ground. JMAX In situations where the ADJ pin is connected to a resistor divider that would pull the ADJ pin above its 7V clamp voltage if the output is pulled high, the ADJ pin input current must be limited to less than 5mA. For example, a resistor divider is used to provide a regulated 1.5V output from the 1.22V reference when the output is forced to 20V. 1763fh 17 For more information www.linear.com/LT1763

LT1763 Series applicaTions inForMaTion The top resistor of the resistor divider must be chosen to When the IN pin of the LT1763-X is forced below the OUT limit the current into the ADJ pin to less than 5mA when pin, or the OUT pin is pulled above the IN pin, input cur- the ADJ pin is at 7V. The 13V difference between output rent will typically drop to less than 2µA. This can happen and ADJ pin divided by the 5mA maximum current into the if the input of the device is connected to a discharged ADJ pin yields a minimum top resistor value of 2.6k. (low voltage) battery and the output is held up by either a backup battery or a second regulator circuit. The state In circuits where a backup battery is required, several of the SHDN pin will have no effect on the reverse output different input/output conditions can occur. The output current when the output is pulled above the input. voltage may be held up while the input is either pulled to ground, pulled to some intermediate voltage or is left open-circuit. Current flow back into the output will follow the curve shown in Figure 7. 100 TJ = 25°C 90 VIN = 0V LT1763-1.5 A) CURRENT FLOWS T (µ 80 INTO OUTPUT PIN EN 70 VOUT = VADJ (LT1763) R R LT1763 U 60 C LT1763-1.8 UT 50 LT1763-2.5 P UT 40 LT1763-3 O SE 30 R E V 20 E R LT1763-5 10 LT1763-3.3 0 0 1 2 3 4 5 6 7 8 9 10 OUTPUT VOLTAGE (V) 1763 F07 Figure 7. Reverse Output Current 1763fh 18 For more information www.linear.com/LT1763

LT1763 Series package DescripTion DE/UE Package 12-Lead Plastic DFN (4mm × 3mm) (Reference LTC DWG # 05-08-1695 Rev D) 0.70 ±0.05 3.30 ±0.05 3.60 ±0.05 2.20 ±0.05 1.70 ± 0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 2.50 REF RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 4.00 ±0.10 R = 0.115 0.40 ± 0.10 (2 SIDES) TYP 7 12 R = 0.05 TYP 3.30 ±0.10 3.00 ±0.10 (2 SIDES) 1.70 ± 0.10 PIN 1 PIN 1 NOTCH TOP MARK R = 0.20 OR (NOTE 6) 0.35 × 45° CHAMFER 6 1 (UE12/DE12) DFN 0806 REV D 0.200 REF 0.75 ±0.05 0.25 ± 0.05 0.50 BSC 2.50 REF 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD NOTE: 1. DRAWING PROPOSED TO BE A VARIATION OF VERSION (WGED) IN JEDEC PACKAGE OUTLINE M0-229 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 THE TOP AND BOTTOM OF PACKAGE 1763fh 19 For more information www.linear.com/LT1763

LT1763 Series package DescripTion Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610 Rev G) .189 – .197 .045 ±.005 (4.801 – 5.004) .050 BSC NOTE 3 8 7 6 5 .245 MIN .160 ±.005 .150 – .157 .228 – .244 (3.810 – 3.988) (5.791 – 6.197) NOTE 3 .030 ±.005 TYP 1 2 3 4 RECOMMENDED SOLDER PAD LAYOUT .010 – .020 × 45° .053 – .069 (0.254 – 0.508) (1.346 – 1.752) .004 – .010 .008 – .010 (0.203 – 0.254) 0°– 8° 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 REV G 0212 4. PIN 1 CAN BE BEVEL EDGE OR A DIMPLE 1763fh 20 For more information www.linear.com/LT1763

LT1763 Series revision hisTory (Revision history begins at Rev G) REV DATE DESCRIPTION PAGE NUMBER G 5/10 Updated Order Information to add MP-grade to all versions of DFN package 2 to 4 Revised Line Regulation section of Electrical Characteristics 5 Consolidated GND and exposed pad descriptions in Pin Descriptions section 14 Added LT3085 to Related Parts 22 H 11/14 Updated Order Information Table to add MP-grade to LT1763-2.5 and LT1763-5 in SO-8 package. 2-3 1763fh Information furnished by Linear Technology Corporation is believed to be accurate and reliable. 21 However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconneFcotior nm oof irtse ciinrcfouirtms aast dioensc wribwedw h.leinreeina rw.cilol nmot/ LinTf1ri7ng6e3 on existing patent rights.

LT1763 Series Typical applicaTion Paralleling of Regulators for Higher Output Current R1 0.1Ω 3.3V IN OUT + + 1A VIN > 3.8V C101µF LT1763S-3E.N3SE C4 C102µF 0.01µF SHDN BYP GND R2 0.1Ω IN OUT C5 LT1763 0.01µF R6 2k BYP SHDN SHDN ADJ GND R3 R4 R7 2.2k 2.2k 1.21k 3 + 8 R5 1 10k 1/2 LT1490 2 – C3 4 0.01µF 1763 TA03 relaTeD parTs PART NUMBER DESCRIPTION COMMENTS LT1120 125mA Low Dropout Regulator with 20µA I Includes 2.5V Reference and Comparator Q LT1121 150mA Micropower Low Dropout Regulator 30µA I , SOT-223 Package Q LT1129 700mA Micropower Low Dropout Regulator 50µA Quiescent Current LT1175 500mA Negative Low Dropout Micropower Regulator 45µA I , 0.26V Dropout Voltage, SOT-223 Package Q LT1521 300mA Low Dropout Micropower Regulator with Shutdown 15µA I , Reverse Battery Protection Q LT1529 3A Low Dropout Regulator with 50µA I 500mV Dropout Voltage Q LT1613 1.4MHz Single-Cell Micropower DC/DC Converter SOT-23 Package, Internally Compensated LT1761 Series 100mA, Low Noise, Low Dropout Micropower Regulators in SOT-23 20µA Quiescent Current, 20µV Noise, ThinSOT™ RMS LT1762 Series 150mA, Low Noise, LDO Micropower Regulators 25µA Quiescent Current, 20µV Noise, MS8 RMS LT1764A 3A, Fast Transient Response Low Dropout Regulator 340mV Dropout Voltage, DD, TO220 LT1962 300mA, Fast Transient Response Low Dropout Regulator 270mV Dropout Voltage, 20µV , MS8 RML LT1963A 1.5A, Fast Transient Response Low Dropout Regulator 340mV Dropout Voltage, 40µV , DD, TO220, S8, SOT-223 RML LT3010 50mA, 80V Low Noise, LDO Micropower Regulator 300mV Dropout Voltage, MS8E LT3021 500mA, Low Voltage, Very Low Dropout Linear Regulator 160mV Dropout Voltage, DFN-8 and SOIC-8 Packages LT3085 500mA Parallelable, Low Noise, Low Dropout Linear Regulator 275mV Dropout Voltage (2 Supply Operation), MSOP-8 and 2mm × 3mm DFN-6 Packages 1763fh 22 Linear Technology Corporation LT 1114 REV H • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 For more information www.linear.com/LT1763 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com/LT1763  LINEAR TECHNOLOGY CORPORATION 1999