LT1431IZ-PBF

LT1431 Programmable Reference FeaTures n n n n n n DescripTion The LT®1431 is an adjustable shunt voltage regulator with 100mA sink capability, 0.4% initial reference voltage tolerance and 0.3% typical temperature stability. On-chip divider resistors allow the LT1431 to be configured as a 5V shunt regulator, with 1% initial voltage tolerance and requiring no additional external components. By adding two external resistors, the output voltage may be set to any value between 2.5V and 36V. The nominal internal current limit of 100mA may be decreased by including one external resistor. A simplified 3-pin version, the LT1431CZ/LT1431IZ, is available for applications as an adjustable reference and is pin compatible with the TL431. Guaranteed 0.4% Initial Voltage Tolerance 0.1Ω Typical Dynamic Output Impedance Fast Turn-On Sink Current Capability, 1mA to 100mA Low Reference Pin Current Available in J8, N8, S8 or 3-Lead TO-92 Z Packages applicaTions n n n Linear Regulators Adjustable Power Supplies Switching Power Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical applicaTion Isolated 5V Regulator + + SWITCHING REGULATOR 5V VIN VREF vs Temperature 2.5025 2.5000 – VREF (V) 5V RTOP V+ COMP COLL 2.4975 2.4950 2.4925 REF + – 2.5V LT1431 GND-S GND-F LT1431 TA01 gm = 4mA/V 2.4900 2.4875 –50 –25 RMID 50 25 75 0 TEMPERATURE (°C) 100 125 LT1431 TA01b 1431fd  LT1431 absoluTe MaxiMuM raTings (Note 1) V+, VCOLLECTOR..........................................................36V VCOMP, RTOP, RMID, VREF .............................................6V GND-F to GND-S ......................................................0.7V Ambient Temperature Range LT1431M ............................................ –55°C to 125°C LT1431I ................................................–40°C to 85°C LT1431C ..................................................0°C TO 70°C Junction Temperature Range LT1431M ............................................ –55°C to 150°C LT1431I .............................................. –40°C to 100°C LT1431C ................................................. 0°C to 100°C Storage Temperature Range .................. –65°C to 150°C Lead Temperature (Soldering, 10 sec)................... 300°C pin conFiguraTion TOP VIEW COLLECTOR 1 COMP 2 V + TOP VIEW 8 REF 7 RMID 6 GND-F 5 GND-S COLLECTOR 1 COMP 2 V + 8 REF 7 RMID 6 GND-F 5 GND-S 3 3 RTOP 4 RTOP 4 J8 PACKAGE 8-LEAD CERDIP TJMAX = 150°C, θJA = 100°C/W TOP VIEW COLLECTOR 1 COMP 2 V+ 3 8 7 6 5 REF RMID GND-F GND-S N8 PACKAGE 8-LEAD PLASTIC DIP TJMAX = 100°C, θJA = 130°C/W BOTTOM VIEW REF ANODE CATHODE RTOP 4 S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 100°C, θJA = 170°C/W Z PACKAGE 3-LEAD TO-92 PLASTIC TJMAX = 100°C, θJA = 150°C/W orDer inForMaTion LEAD FREE FINISH LT1431CN8#PBF LT1431IN8#PBF LT1431CS8#PBF LT1431IS8#PBF LT1431MJ8#PBF LT1431CZ#PBF LT1431IZ#PBF TAPE AND REEL LT1431CN8#TRPBF LT1431IN8#TRPBF LT1431CS8#TRPBF LT1431IS8#TRPBF LT1431MJ8#TRPBF LT1431CZ#TRPBF LT1431IZ#TRPBF PART MARKING LT1431 CN8 LT1431 IN8 LT1431 LT1431I LT1431 MJ8 LT1431 CZ LT1431 IZ PACKAGE DESCRIPTION 8-Lead Plastic DIP 8-Lead Plastic DIP 8-Lead Plastic SO 8-Lead Plastic SO 8-Lead CERDIP 3-Lead TO-92 Plastic 3-Lead TO-92 Plastic TEMPERATURE RANGE 0°C to 70°C –40°C to 85°C 0°C to 70°C –40°C to 85°C –55°C to 125°C 0°C to 70°C –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard 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/ 1431fd  LT1431 elecTrical characTerisTics SYMBOL VREF ∆VREF/∆T PARAMETER Reference Voltage Reference Drift The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. IK = 10mA unless otherwise specified (Note 2) LT1431I, LT1431M CONDITIONS VKA = 5V, IK = 2mA, (Note 3) l LT1431C MIN TYP MAX UNITS V V ppm/°C 0.5 1.0 1.2 1.0 1 2 1 2 0.2 100 260 mV/V µA µA mA µA µA µA µA Ω mA V MIN TYP MAX 2.490 2.500 2.510 2.490 2.500 2.510 2.465 2.535 2.480 2.520 50 0.2 0.2 0.5 1.0 1.5 1.0 1 15 1 5 0.2 80 360 30 0.2 0.2 0.6 VKA = 5V, IK = 2mA IK = 2mA, VKA = 3V to 36V VKA = 5V, TA = 25°C l l ∆VREF/∆VKA Voltage Ratio, Reference to Cathode (Open-Loop Gain) |IREF| IMIN |IOFF| |ILEAK| |ZKA| ILIM Reference Input Current Minimum Operating Current Off-State Cathode Current l VKA = VREF to 36V VKA = 36V, VREF = 0V l 0.6 Off-State Collector Leakage Current VCOLL = 36V, V+ = 5V, VREF = 2.4V l Dynamic Impedance Collector Current Limit 5V Reference Output VKA = VREF, IK = 1mA to 100mA, f ≤ 1kHz VKA = VREF + 50mV Internal Divider Used, IK = 2mA l 4.950 5.000 5.050 4.950 5.000 5.050 Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: VKA is the cathode voltage of the LT1431CZ/IZ and corresponds to V+ of the LT1431CN8/IN8/CS8/IS8. IK is the cathode current of the COLLECTOR of the LT1431CN8/ IN8/CS8/IS8. Note 3: The LT1431 has bias current cancellation which is effective only for VKA ≥ 3V. A slight (≈2mV) shift in reference voltage occurs when VKA drops below 3V. For this reason, these tests are not performed at VKA = VREF. LT1431CZ/IZ and corresponds to I(V+) + I 1431fd  LT1431 Typical perForMance characTerisTics 1000 900 800 700 IK (µA) 600 500 IMIN VREF (V) 2.5V Reference IK vs VKA 2.505 2.504 2.503 2.502 2.501 2.500 2.499 2.498 2.497 2.496 VREF and IREF vs V + 3.5 3.0 2.5 2.0 2.505 2.504 2.503 2.502 VREF (V) 2.501 2.500 2.499 2.498 2.497 2.496 2.495 IREF (µA) VREF and IREF vs V + 3.5 3.0 2.5 2.0 1.5 IREF (µA) VREF IREF 1.5 1.0 0.5 0 400 300 VREF 1.0 0.5 0 200 100 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 VKA (V) LT1431 TPC01 –0.5 –1.0 IREF –0.5 –1.0 –1.5 2.495 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 + (V) V LT1431 TPC02 0 4 8 12 16 20 24 28 32 36 40 V+ (V) LT1431 TPC03 –1.5 2.5025 2.5000 2.4975 VREF (V) 2.4950 2.4925 2.4900 VREF and IREF vs Temperature VREF ILIMIT vs Temperature with External Resistor 1.00 0.66 ILIMIT (NORMALIZED) 0.33 IREF (µA) 1.250 ILIMIT = 1.125 1.000 0.875 0.750 0.625 0.500 –50 –25 VSAT (V) 0.7 AT 25°C RLIM + 3.6 1.20 1.00 0.80 0.60 COLLECTOR VSAT vs Temperature vs Current ICOLL = 100mA IREF 0 ICOLL = 50mA 0.40 0.20 0 –50 –25 ICOLL = 20mA ICOLL = 10mA 50 25 75 0 TEMPERATURE (°C) 100 125 –0.33 –0.66 –1.00 125 2.4875 –50 –25 50 25 75 0 TEMPERATURE (°C) 100 LT1431 TPC04 50 25 75 0 TEMPERATURE (°C) 100 125 LT1431 TPC05 LT1431 TPC06 Propagation Delay vs Overdrive 150 135 PROPAGATION DELAY (µs) 120 105 90 75 60 45 30 15 0 0 50 OUTPUT HIGH-TO-LOW OUTPUT LOW-TO-HIGH 150 100 OVERDRIVE (mV) 200 250 VREF ± OVERDRIVE 5V 1k 3 LT1431 5 6 1 OUTPUT Voltage Gain and Phase vs Frequency 140 120 REF-TO-COLL 1k LOAD AV (dB) 100 80 60 40 20 0 –20 100 1k 10k 100k FREQUENCY (Hz) 1M AV PHASE 180 135 1010 109 REF-TO-COLL gm (µ ) 108 107 106 105 104 103 Transconductance and Phase vs Frequency (REF to COLL) 180 135 PHASE 90 45 0 –45 –90 –135 1k 10k 100k FREQUENCY (Hz) 1M –180 10M PHASE (DEG) 90 45 0 –45 –90 –135 –180 10M PHASE (DEG) gm 102 100 LT1431 TPC07 LT1431 TPC08 LT1431 TPC09 1431fd  LT1431 Typical perForMance characTerisTics 104 Transconductance and Phase vs Frequency (Ref to Comp) PHASE gm 20 0 –20 ZKA ( ) –40 PHASE (DEG) 1.4 1.2 1.0 0.8 0.6 0.4 0.2 Dynamic Impedance vs Frequency IK ≤ 100mA 3.0 2.5 2.0 VCOMP (V) 1.5 1.0 0.5 VCOMP vs Temperature vs ICOLL REF-TO-COLL gm (µ ) 3 103 ICOLL = 100mA ICOLL = 10mA 103 –60 –80 3 102 –100 –120 0.1 100 1k 10k 100k FREQUENCY (Hz) 1M –140 10M 0 100 LT1431 TPC10 1k 10k FREQUENCY (Hz) 100k LT1431 TPC11 0 –50 –25 50 25 75 0 TEMPERATURE (°C) 100 125 LT1431 TPC12 ICOMP vs VCOMP vs VREF 600 500 NOISE (nV/√Hz) 400 ICOMP (µA) 300 200 VREF = 2.53V 100 0 0 VREF = 5V VREF = 4V VREF = 3V 1000 Noise vs Frequency 0.1Hz to 10Hz Noise 500 0 0.5 1.0 1.5 2.0 VCOMP (V) 2.5 3.0 3.5 NOISE VOLTAGE (50µV/DIV) 1 10 100 1k FREQUENCY (Hz) 10k 100k LT1431 G14 0 1 LT1431 TPC13 4 3 2 TIME (MINUTES) 5 6 LT1431 TPC15 1431fd  LT1431 pin FuncTions COLL (Pin 1): Open collector of the output transistor. The maximum pin voltage is 36V. The saturation voltage at 100mA is approximately 1V. COMP (Pin 2): Base of the driver for the output transistor. This pin allows additional compensation for complex feedback systems and shutdown of the regulator. It must be left open if unused. V + (Pin 3): Bias voltage for the entire shunt regulator. The maximum input voltage is 36V and the minimum to operate is equal to VREF (2.5V). The quiescent current is typically 0.6mA. RTOP (Pin 4): Top of the on-chip 5k-5k resistive divider that guarantees 1% accuracy of operation as a 5V shunt regulator with no external trim. The pin is tied to COLL for self-contained 5V operation. It may be left open if unused. See note on parasitic diodes below. GND-S (Pin 5): Ground reference for the on-chip resistive divider and shunt regulator circuitry except for the output transistor. This pin allows external current limit of the output transistor with one resistor between GND-F (force) and GND-S (sense). GND-F (Pin 6): Emitter of the output transistor and substrate connection for the die. RMID (Pin 7): Middle of the on-chip resistive divider string between RTOP and GND-S. The pin is tied to REF for selfcontained 5V operation. It may be left open if unused. REF (Pin 8): Control pin of the shunt regulator with a 2.5V threshold. If V+ > 3V, input bias current cancellation reduces IB to 0.2µA typical. COMP RTOP, RMID, and REF have static discharge protection , circuits that must not be activated on a continuous basis. Therefore, the absolute maximum DC voltage on these pins is 6V, well beyond the normal operating conditions. As with all bipolar ICs, the LT1431 contains parasitic diodes which must not be forward biased or else anomalous behavior will result. Pin conditions to be avoided are RTOP below RMID in voltage and any pin below GND-F in voltage (except for GND-S). The following pin definitions apply to the Z package. CATHODE: Corresponds to COLL and V+ tied together. ANODE: Corresponds to GND-S and GND-F tied together. REF: Corresponds to REF . block DiagraM RTOP 4 5k REF 8 V + 3 COMP 2 COLLECTOR 1 + – 5k 2.5V gm = 4mA/V RMID 7 5 GND-SENSE 6 GND-FORCE LT1431 BD 1431fd  LT1431 applicaTions inForMaTion Frequency Compensation As a shunt regulator, the LT1431 is stable for all capacitive loads on the COLL pin. Capacitive loading between 0.01µF and 18µF causes reduced phase margin with some ringing under transient conditions. Output capacitors should not be used arbitrarily because output noise is not necessarily reduced. Excess capacitance on the REF pin can introduce enough phase shift to induce oscillation when configured as a reference >2.5V. This can be compensated with capacitance between COLL and REF (phase lead). More complicated feedback loops may require shaping of the frequency response of the LT1431 with dominant pole or pole-zero compensation. This can be accomplished with a capacitor or series resistor and capacitor between COLL and COMP . The compensation schemes mentioned above use voltage feedback to stabilize the circuits. There must be voltage gain at the COLL pin for them to be effective, so the COLL pin must see a reasonable AC impedance. Capacitive loading of the COLL pin reduces the AC impedance, voltage gain, and frequency response, thereby decreasing the effectiveness of the compensation schemes, but also decreasing their necessity. Typical applicaTions 2.5V Reference 3-Pin Package VIN RL 2.5V CATHODE LT1431Z REF GND-S LT1431 TA02 2.5V Reference 8-Pin Package VIN V+ LT1431 RL 2.5V COLL REF VIN V+ RTOP 5V Reference RL 5V COLL LT1431 REF RMID GND-F LT1431 TA04 ANODE GND-F LT1431 TA03 GND-S Increasing 5V Reference VIN R V+ RTOP GND-S LT1431 RL 5V + ∆ COLL REF RMID GND-F LT1431 TA05 Programmable Reference with Adjustable Current Limit VIN V+ LT1431 GND-S RLIM RL VOUT = 1 + R1 VREF R2 COLL REF R2 GND-F ILIMIT = 0.7 AT 25°C RLIM + 3.6 LT1431 TA06 R1 () ∆ = R • (0.5mA) ±25% PROCESS TOLERANCE ∆ ≤ 500mV 1431fd  LT1431 Typical applicaTions PNP Low Dropout 5V Regulator* VIN 0.1µF 20 ** 2W 1k 150 2 COMP V+ RTOP GND-S 5 LT1431 0.015µF 1 COLL REF RMID GND-F 6 2N2219 47 MJE2955 3 4 8 7 MEASURED DROPOUT VOLTAGE 420mV AT 4A 190mV AT 2A 95mV AT 1A 60mV AT 0.5A *NO SHORT-CIRCUIT PROTECTION **MAY BE INCREASED AT LOWER WATTAGE FOR LOWER OUTPUT CURRENTS + 5V 330µF LT1431 TA07 FET Low Dropout 5V Regulator with Current Limit 12V MTP50N05EL MTM25N05L 0.002 * VIN ≥ 5.2V + D 47µF G S – 1.5k 7 2 LT1006 LT1006 + 3 4 + 5V, 2.5A 47µF 5 1N4148 1 COLL V+ RTOP GND-S 5 LT1431 REF RMID GND-F 6 LT1431 • TA08 6 Measured Dropout Voltages ILOAD 2A 1A 0.5A MTP50N05EL 47mV 22mV 11.5mV MTM25N05L 145mV 73mV 37mV 3 4 8 7 *1.5" #23 SOLID COPPER WIRE ~0.002 3A LIMIT 1431fd  LT1431 Typical applicaTions 12V to 5V Buck Converter with Foldback Current Limit* PULSE ENGINEERING #PE-51515 VIN VIN VOUT LT1089 HI-SIDE SWITCH GND MBR735 80 VIN = 9V VIN = 12V Buck Converter Efficiency 70 EFFICIENCY (%) 100 0.5W 60 LOGIC IN VIN = 15V 50 5k 2 COMP V+ RTOP GND-S 5 LT1431 1500pF 1 COLL REF RMID 40 8 7 30 0 1 2 3 4 ILOAD (A) 5 6 7 8 3 4 GND-F 6 LT1431 TA10 *CONTACT LTC FOR HIGH EFFICIENCY SWITCHING REGULATORS + 5V, 7A 3300µF LT1431 TA09 Isolated 5V to ± 15V Flyback Converter COILTRONICS CTX02-11934 4.5V TO 5.5V 0.47µF 3k MUR105 6, 7 9 MUR105 –15V, 70mA C* 15k Fully Loaded Output Ripple vs Filtering C* LT1172 30mVP-P LT1072 40mVP-P + 210µF • 4, 5 • 2 10 + 50µF VIN LT1172 OR LT1072 VOUT GND VC 1 • MUR105 + 1.5k 4N36 MEASURED EFFICIENCY LT1172 67.8% AT 2.2WOUT LT1072 68.6% AT 2.2WOUT LT1071 61.1% AT 4.4WOUT 0.68µF 2.4k 0.1µF 1 20k 2 COLL LT1431 COMP GND-S 5 + L* + 100µF + 100µF 6mVP-P 8mVP-P *L BELL INDUSTRIES J.W. MILLER DIVISION 9310-36 10µH, 450mA 15V, 70mA C* LT1431 TA12 3 V+ 8 REF 13.3k 2.7k GND-F 6 LT1431 TA11 1431fd  LT1431 Typical applicaTions 5V Power Supply Monitor with ± 500mV Window and 50mV Hysteresis 6 1k 6k* 1N4148 1k 4k* 5 4 VOUT 3 2 1 0 Transfer Function “HIGH” FOR OVER VOLTAGE OR UNDER VOLTAGE V+ LT1431 GND-S COLL REF 5k V+ LT1431 GND-S COLL REF 5k GND-F 10 ** GND-F 10 ** *DETERMINES WINDOW SIZE V = (R – 5k)(0.5mA) **SETS HYSTERESIS LT1431 TA13 0 1 2 3 VIN 4 5 6 LT1431 TA14 High Efficiency Buck Converter E = 85% to 89% VIN 1 + C1 220µF 35V D1 BAT85 5 4 VSW LT1170 2 FB GND VC 3 D4 BAT85 1 R2 1k C3 0.1µF C4 0.033µF VIN C5 0.047µF R1 470k BOLD LINES INDICATE HIGH CURRENT PATHS *1% FILM RESISTORS C1: NICHICON UPL1V221MPH C3, C4, C5: WIMA MKS-2 C6: NICHICON UPL1C471MPH6 D1, D2: PHILIPS BAT85 D3: MOTOROLA MBR330 L1: COILTRONICS CTX50-3-MP + C2 4.7µF 35V TANT D2 BAT85 Q2 2N3904 Q1 VN2222LL Q3 2N3904 2 COMP 1 OFF 1 RUN = 0 SHUTDOWN > 3V R3 10k RTN 2 R4 100 R5 680 R8* 24.9k COLL 3+ 8 V REF LT1431CN8 4 7 RTOP RMID GND-S GND-F 5 6 NOTES: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTANCES ARE IN , 0.25W, 5% 2. ALL CAPACITANCES ARE IN µF, 50V, 10% 3. SHUTDOWN LOGIC STATE MUST BE DEFINED BY A LOGIC GATE OR BY TYING TO GND 0 + D3 L1 MBR330 50µH 3A 0.12 ESR C6 470µF 16V 5V 2.5A R6* 23.7k R7* 24.9k 1431 TA15 1431fd LT1431 scheMaTic DiagraM Q5 R1 35k R2 35k 4X Q7 3X Q13 3 Q17 V + Q1 Q2 Q3 Q11 Q10 Q12 COMP 2 Q6 2X 8 REF Q9 5X R11 11k R7 2.5k R3 5k R MID 7 R9 2.5k Q14 C1 22pF R12 1k R15 5k R13 6.5k C3 6pF R17 1.5k C4 1pF COLLECTOR 1 R6 8.5k Q4 C2 65pF Q20 2X Q22 45X RTOP 4 Q18 Q19 Q15 Q16 R10 340 R21 100k R16 11 R14 11 Q8 10X R20 5k Q21 2.5X R4 5k GND-SENSE 5 R5 5k R8 600 R18 50k R19 3.6 6 GND-FORCE LT1431 SD01 package DescripTion J8 Package 8-Lead CERDIP (Narrow .300 Inch, Hermetic) (Reference LTC DWG # 05-08-1110) .405 (10.287) MAX 8 7 6 5 .300 BSC (7.62 BSC) CORNER LEADS OPTION (4 PLCS) .200 (5.080) MAX .015 – .060 (0.381 – 1.524) .005 (0.127) MIN .008 – .018 (0.203 – 0.457) 0° – 15° .023 – .045 (0.584 – 1.143) HALF LEAD OPTION .045 – .068 (1.143 – 1.650) FULL LEAD OPTION .025 (0.635) RAD TYP 1 2 3 4 .220 – .310 (5.588 – 7.874) J8 0801 .045 – .065 (1.143 – 1.651) .014 – .026 (0.360 – 0.660) .100 (2.54) BSC NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS .125 3.175 MIN 1431fd  LT1431 package DescripTion N8 Package 8-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .400* (10.160) MAX 8 7 6 5 .300 – .325 (7.620 – 8.255) .045 – .065 (1.143 – 1.651) .130 ± .005 (3.302 ± 0.127) .008 – .015 (0.203 – 0.381) .065 (1.651) TYP .255 ± .015* (6.477 ± 0.381) .120 (3.048) .020 MIN (0.508) MIN .018 ± .003 (0.457 ± 0.076) ( +.035 .325 –.015 8.255 +0.889 –0.381 ) 1 2 3 4 N8 1002 .100 (2.54) BSC INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) NOTE: 1. DIMENSIONS ARE S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .045 ±.005 8 .189 – .197 (4.801 – 5.004) NOTE 3 7 6 5 .050 BSC .245 MIN .160 ±.005 .228 – .244 (5.791 – 6.197) .150 – .157 (3.810 – 3.988) NOTE 3 .030 ±.005 TYP RECOMMENDED SOLDER PAD LAYOUT .010 – .020 × 45° (0.254 – 0.508) .008 – .010 (0.203 – 0.254) 0°– 8° TYP 1 2 3 4 .053 – .069 (1.346 – 1.752) .004 – .010 (0.101 – 0.254) .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN INCHES (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) .014 – .019 (0.355 – 0.483) TYP .050 (1.270) BSC SO8 0303 1431fd  LT1431 revision hisTory REV D DATE 4/10 DESCRIPTION M-Grade Parts Re-Released. Obsolete Package Shading Removed (Revision history begins at Rev D) PAGE NUMBER 2, 11 1431fd Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.  LT1431 package DescripTion Z Package 3-Lead Plastic TO-92 (Similar to TO-226) (Reference LTC DWG # 05-08-1410 Rev C) .180 (4.572 .005 0.127) .060 .005 (1.524 0.127) DIA .180 (4.572 .005 0.127) .90 (2.286) NOM .500 (12.70) MIN .050 UNCONTROLLED (1.270) LEAD DIMENSION MAX 5 NOM .050 (1.27) BSC BULK PACK .016 (0.406 .003 0.076) .015 (0.381 .002 0.051) Z3 (TO-92) 1008 REV C .098 +.016/–.04 (2.5 +0.4/–0.1) 2 PLCS TO-92 TAPE AND REEL REFER TO TAPE AND REEL SECTION OF LTC DATA BOOK FOR ADDITIONAL INFORMATION .060 (1.524 .010 0.254) 3 2 1 .140 (3.556 .010 0.127) 10 NOM relaTeD parTs PART NUMBER LTC 3722 ® DESCRIPTION Synchronous Full-Bridge Controller Synchronous Push-Pull PWM Controller SOT-23 Flyback Controller Synchronous Flyback Controller Opto-Coupler Driver in SOT-23 COMMENTS Zero Voltage Switching, Adjustable 2VS Timing 1.5A Sink, 1A Source Output Drivers, Adjustable Dead Time Adjustable Slope Compensation, 200kHz Operation Excellent Cross Regulation, High Efficiency Overshoot Control, 600mV Reference, High Bandwidth Error Amplifier LTC3723 LTC3803 LTC3806 LT4430 LTC3900/LTC3901 Synchronous Rectifiers for Forward and Push-Pull Converters Programmable Time Out, Reverse Inductor Current Sense 1431fd  Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● LT 0410 REV D • PRINTED IN USA www.linear.com  LINEAR TECHNOLOGY CORPORATION 1992