LT1171 LINER [Linear Technology], LT1171 Datasheet
LT1171
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LT1171 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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... ORDER PART NUMBER LT1170MK LT1170CK LT1171MK LT1171CK 5-LEAD PLASTIC TO-220 LT1172MK LT1172CK LT1170CT/LT1170HVCT LT1171CT/LT1171HVCT LT1172CT/LT1172HVCT Based on continuous operation 125 C for intermittent fault conditions. JMAX ORDER PART NUMBER LT1171HVCQ LT1172CQ LT1172HVIQ ORDER PART TOP VIEW NUMBER LT1172CSW ...
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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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... IN (t)(f) buck and inverting mode R = Inductor DC resistance I = 10A for LT1170, 5A for LT1171, and 2.5A for LT1172 Output catch diode forward voltage 0 100kHz switching frequency Maximum input voltage can be increased by increasing R or Vf. External current limiting such as that shown in AN19, Figure 39, will provide protection up to the full supply voltage rating ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Line Regulation 150 – –1 –2 –3 –4 – ...
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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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... LT1170/LT1171/LT1172 to disconnect the main error amplifier output and connects the output of the flyback amplifier to the comparator input. The LT1170/ LT1171/LT1172 will then regulate the value of the flyback pulse with respect to the supply voltage.* This flyback pulse is directly proportional to output voltage in the traditional transformer coupled flyback topology regula- tor ...
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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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LT1 170/LT1 171/LT1172 U TYPICAL APPLICATIO 20V TO 30V D3 25V 1W D2 MUR110 C4* LT1170 100 GND C R3 1.5k C2 0.15 F *REQUIRED IF INPUT LEADS 2" ...
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... IN AN19, FIGURE 39, SHOULD BE ADDED WITH C1 REDUCED TO 200pF. * REQUIRED IF INPUT LEADS 2" ** PULSE ENGINEERING 92114 COILTRONICS 50-2-52 + C3* 100 F OPTIONAL INPUT FILTER –20V (Note that maximum output currents are divided by 2 for LT1171 for LT1172 1170/1/2 TA05 † L1 OPTIONAL C3 OUTPUT ...
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... R1 R4 1N914 10. † 1.24k 2 F 1000 0 High Efficiency Constant Current Charger V SW LT1171 GND 0. 0.47 F 2N3904 MBR340 22k 1k Backlight CCFL Supply (see AN45 for details) L1** 1N5818 300 H A Q1* ...
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U TYPICAL APPLICATIO 2 C5* 100 F + C4* 470 –15V * REQUIRED IF INPUT LEADS 2" Positive Buck Converter * REQUIRED IF INPUT LEADS 2" ** PULSE ENGINEERING ...
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LT1 170/LT1 171/LT1172 U TYPICAL APPLICATIO 20V TO 30V GND 330 F 35V C6 0.02 F MBR330p MODE LOGIC <0.3V = NORMAL MODE >2.5V = SHUTDOWN OPEN = BURST MODE 14 Forward Converter ...
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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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PACKAGE DESCRIPTIO 0.390 – 0.415 (9.906 – 10.541) 0.230 – 0.270 (5.842 – 6.858) 0.460 – 0.500 (11.684 – 12.700) 0.330 – 0.370 (8.382 – 9.398) 0.067 BSC 0.028 – 0.038 (1.70) (0.711 – 0.965) Information furnished by Linear Technology ...
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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 ...