LT1170 Linear Technology, LT1170 Datasheet
LT1170
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LT1170 Summary of contents
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... This manual contains a comprehensive discussion of both the LT1070 and the external components used with it, as well as complete formulas for calculating the values of these components. The manual can also be used for the LT1170/LT1171/LT1172 by factoring in the higher TM frequency. A CAD design program called SwitcherCAD is also available ...
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... LT1170/71/72M ......................... – 150 C LT1170/71/72HVC, LT1170/71/72C (Oper.) .............. 100 C LT1170/71/72HVC LT1170/71/72C (Sh. Ckt.) .......... 125 C LT1170/71/72HVI, LT1170/71/72I (Oper.) .......... – 100 C LT1170/71/72HVI, LT1170/71/72I (Sh. Ckt.) ...... – 125 ORDER PART NUMBER ...
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... LT1170/LT1171/LT1172 IN MAX I = 1.5mA LT1170HV/LT1171HV/LT1172HV SW LT1172S8 LT1170 LT1171 LT1172 LT1170 LT1171 LT1172 Duty Cycle = 50% Duty Cycle = 50% Duty Cycle = 80% (Note 4) Duty Cycle = 50% Duty Cycle = 50% Duty Cycle = 80% (Note 4) Duty Cycle = 50% Duty Cycle = 50% Duty Cycle = 80% (Note 4) LT1 170/LT1 171/LT1172 = V , output pin open, unless otherwise noted. ...
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... Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: Minimum effective switch “on” time for the LT1170/71/72 (in current limit only) is 0.6 s. This limits the maximum safe input voltage during an output shorted condition. Buck mode and inverting mode input voltage during ...
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... SWITCH CURRENT (A) 1170/1/2 G08 * AVERAGE LT1170 POWER SUPPLY CURRENT IS FOUND BY MULTIPLYING DRIVER CURRENT BY DUTY CYCLE, THEN ADDING QUIESCENT CURRENT. Error Amplifier Transconductance 5000 I (V PIN) C 4500 (FB PIN) 4000 3500 3000 2500 ...
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LT1 170/LT1 171/LT1172 W U TYPICAL PERFOR A CE CHARACTERISTICS Idle Supply Current vs Temperature 0. 60V SUPPLY SUPPLY –75 –50 ...
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... AND LT1171 ONLY) protection under output overload or short conditions. A low dropout internal regulator provides a 2.3V supply for all internal circuitry on the LT1170/LT1171/LT1172. This low dropout design allows input voltage to vary from 3V to 60V with virtually no change in device performance. A 100kHz oscillator is the basic clock for all internal timing. ...
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... Likewise, a capacitor coupled external clamp will provide soft start. Switch duty cycle goes to zero if the V pin is pulled to ground through a C diode, placing the LT1170/LT1171/LT1172 in an idle mode. Pulling the V pin below 0.15V causes total regulator C shutdown, with only 50 A supply current for shutdown circuitry biasing ...
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... Synchronizing occurs when the V with an external transistor. To avoid disturbing the DC characteristics of the internal error amplifier, the width of the synchronizing pulse should be under 0 sets the pulse width at 0.2 s. The effect of a synchronizing pulse on the LT1170/LT1171/LT1172 amplifier offset can be calculated from ...
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... SECONDARY VOLTAGE N • AREA “c” = AREA “d” TO MAINTAIN ZERO DC VOLTS ACROSS SECONDARY PRI PRIMARY CURRENT PRI SECONDARY CURRENT 0 I PRI LT1170 SWITCH CURRENT 0 I PRI SNUBBER DIODE CURRENT 0 (I )(L ) PRI SNUB + 1N914 TANTALUM ...
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... TA06 External Current Limit LT1170 + – V GND 1000pF R S NOTE THAT THE LT1170 1170/1/2 TA08 GND PIN IS NO LONGER – COMMON 1000 F LOAD R1 4.64k –5.2V 4.5A R4 12k Q1 2N3906 OPTIONAL + C4 OUTPUT 200 F FILTER L2 ...
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... LT1 170/LT1 171/LT1172 U TYPICAL APPLICATIO S † D3 1N4001 LT1170 1 F GND INPUT VOLTAGE > < 35V BAT D1 1N5819 2.2 F 200 F 35V 35V TANTALUM RUN = 0V SHUTDOWN = 5V R6 78k † INPUT VOLTAGE 4.5V TO 20V TANT LT1172 E1 GND Positive-to-Negative Buck-Boost Converter † ...
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... C3 LT1170 GND 1.24k 3. 0.22 F Driving High Voltage NPN C1 D2 R2** R1 LT1170 * SETS I ** SETS I GND LT1 170/LT1 171/LT1172 OPTIONAL C5 OUTPUT 200 F FILTER D2 1N914 L1 5V, 4. 100mA 1000 F MINIMUM 1170/1/2 TA13 ...
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... OPEN = BURST MODE 14 Forward Converter LT1170 330 High Efficiency 5V Buck Converter LT1170 FB V GND D2 C 1N4148 + 4.7 F 680 0.03 F TANT 0 DIODE LIM LT1432 V MODE ...
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PACKAGE DESCRIPTIO CORNER LEADS OPTION 0.045 – 0.068 (1.143 – 1.727) FULL LEAD OPTION 0.300 BSC (0.762 BSC) 0.008 – 0.018 (0.203 – 0.457) NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS U Dimensions in inches (millimeters) ...
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LT1 170/LT1 171/LT1172 PACKAGE DESCRIPTIO 0.760 – 0.775 0.320 – 0.350 (19.30 – 19.69) (8.13 – 8.89) 0.420 – 0.480 (10.67 – 12.19) 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) +0.035 0.325 –0.015 +0.889 8.255 ...
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PACKAGE DESCRIPTIO 0.060 0.256 (1.524) (6.502) 0.060 0.183 (1.524) (4.648) 0.075 (1.905) 0.300 (7.620) BOTTOM VIEW OF DD PAK HATCHED AREA IS SOLDER PLATED COPPER HEAT SINK 0.010 – 0.020 (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.016 ...
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LT1 170/LT1 171/LT1172 PACKAGE DESCRIPTIO 0.291 – 0.299** (7.391 – 7.595) 0.010 – 0.029 (0.254 – 0.737) 0.009 – 0.013 NOTE 1 (0.229 – 0.330) 0.016 – 0.050 (0.406 – 1.270) NOTE: 1. PIN 1 IDENT, NOTCH ON TOP AND ...
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... 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U Dimensions in inches (millimeters) unless otherwise noted. ...
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... LT1 170/LT1 171/LT1172 U TYPICAL APPLICATIO V IN 28V LT1170 GND + C5* 100 F * REQUIRED IF INPUT LEADS 2" RELATED PARTS PART NUMBER DESCRIPTION LT1070/LT1071/LT1072 5A/2.5A/1.25A High Efficiency Switching Regulators LT1074/LT1076 5.5A/2A Step-Down Switching Regulators LT1082 1A, High Voltage, High Efficiency Switching Regulator LT1268/LT1268B 7.5A, 150kHz Switching Regulators LT1269/LT1271 ...