LT1172IS8#TRPBF Linear Technology, LT1172IS8#TRPBF Datasheet
LT1172IS8#TRPBF
Specifications of LT1172IS8#TRPBF
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LT1172IS8#TRPBF Summary of contents
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... L, LT, LTC, LTM, Linear Technology, the Linear logo and SwitcherCAD are registered ® is also available. trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Maximum Output Power* 100 L2 ...
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LT1170/LT1171/LT1172 ABSOLUTE MAXIMUM RATINGS Supply Voltage LT1170/LT1171/LT1172HV (Note 2) .......................60V LT1170/LT1171/LT1172 (Note 2) ............................40V Switch Output Voltage LT1170/LT1171/LT1172HV .....................................75V LT1170/LT1171/LT1172 .........................................65V LT1172S8 ..............................................................60V Feedback Pin Voltage (Transient, 1ms) ................... ±15V Storage Temperature Range .................. –65°C to 150°C Lead Temperature (Soldering, ...
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... LT1170MK#TRPBF LT1170CK#PBF (OBSOLETE) LT1170CK#TRPBF LT1171MK#PBF (OBSOLETE) LT1171MK#TRPBF LT1171CK#PBF (OBSOLETE) LT1171CK#TRPBF LT1172MK#PBF (OBSOLETE) LT1172MK#TRPBF LT1172CK#PBF (OBSOLETE) LT1172CK#TRPBF LT1172CN8#PBF LT1172CN8#TRPBF LT1172IN8#PBF LT1172IN8#TRPBF LT1172CS8#PBF LT1172CS8#TRPBF LT1172IS8#PBF LT1172IS8#TRPBF LT1170CQ#PBF LT1170CQ#TRPBF LT1170IQ#PBF LT1170IQ#TRPBF LT1170HVCQ#PBF LT1170HVCQ#TRPBF LT1171CQ#PBF LT1171CQ#TRPBF LT1171IQ#PBF LT1171IQ#TRPBF LT1171HVCQ#PBF LT1171HVCQ#TRPBF LT1171HVIQ#PBF LT1171HVIQ#TRPBF LT1172CQ#PBF LT1172CQ#TRPBF LT1172HVCQ#PBF ...
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LT1170/LT1171/LT1172 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Reference Voltage REF I Feedback Input Current B g Error Amplifier Transconductance m Error Amplifier Source or Sink Current Error Amplifier Clamp Voltage Reference Voltage Line Regulation ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER DC Maximum Switch Duty Cycle MAX Shutdown Mode Supply Current Shutdown Mode Threshold Voltage Flyback Sense Delay Time (Note 5) Note 1: Stresses beyond those listed under Absolute Maximum ...
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LT1170/LT1171/LT1172 TYPICAL PERFORMANCE CHARACTERISTICS Switch Current Limit vs Duty Cycle 25°C –55°C 8 125° DIVIDE VERTICAL SCALE BY TWO FOR LT1171, BY FOUR FOR LT1172 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Shutdown Mode Supply Current 200 180 160 140 T = 150°C J 120 100 80 60 –55°C ≤ T ≤ 125° 100 V ...
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LT1170/LT1171/LT1172 TYPICAL PERFORMANCE CHARACTERISTICS Transconductance of Error Amplifier 7000 6000 5000 4000 g 3000 2000 1000 0 –1000 1k 10k 100k FREQUENCY (Hz) BLOCK DIAGRAM V IN 2.3V REG 100kHz OSC MODE SELECT – FB ERROR AMP + 1.24V REF ...
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OPERATION The LT1170/LT1171/LT1172 are current mode switchers. This means that switch duty cycle is directly controlled by switch current rather than by output voltage. Referring to the block diagram, the switch is turned “on” at the start of each oscillator ...
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LT1170/LT1171/LT1172 OPERATION Care should be taken for miniDIP applications to ensure that the worst case input voltage and load current conditions do not cause excessive die temperatures. The following formulas can be used as a rough guide to calculate LT1172 ...
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OPERATION With t = 0.2μ 150kHz 1.5V, and R3 = 2k, offset voltage shift is ≈ 3.8mV. This is not particularly bother- some, but note that high offsets could result if R3 were ...
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LT1170/LT1171/LT1172 TYPICAL APPLICATIONS E2 E1 OPTIONAL VN2222 SHUTDOWN D2 ER82.004 600mA SCHOTTKY. OTHER FAST SWITCHING TYPES MAY BE USED AND BATTERY MAY BE TIED TOGETHER. MAXIMUM VALUE FOR V IN BATTERY VOLTAGES, HIGHEST EFFICIENCY IS OBTAINED ...
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TYPICAL APPLICATIONS Negative-to-Positive Buck-Boost Converter C4* LT1170 100μF OPTIONAL INPUT FILTER V GND –20V * REQUIRED IF INPUT LEADS ≥ 2" PULSE ENGINEERING 92114, COILTRONICS 50-2-52 ** † THIS CIRCUIT IS OFTEN USED TO ...
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LT1170/LT1171/LT1172 TYPICAL APPLICATIONS † D3 1N4001 470Ω LT1170 1μF V GND INPUT VOLTAGE > < 35V BAT D1 1N5819 2.2 μ F 200 μ F 35V 35V TANTALUM ...
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TYPICAL APPLICATIONS 2.2μF + C5* 100μF + C4* 470μF L1 50μ –15V * REQUIRED IF INPUT LEADS ≥ 2" Positive Buck Converter * REQUIRED IF INPUT LEADS ≥ 2" ** PULSE ENGINEERING 92114 ...
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LT1170/LT1171/LT1172 TYPICAL APPLICATIONS V IN 20V TO 30V GND 330μF 35V C6 0.02μF MBR330p MODE LOGIC <0.3V = NORMAL MODE >2.5V = SHUTDOWN OPEN = BURST MODE 16 Forward Converter ...
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PACKAGE DESCRIPTION CORNER LEADS OPTION .045 – .068 (1.143 – 1.650) FULL LEAD OPTION .300 BSC (7.62 BSC) .008 – .018 (0.203 – 0.457) NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS .760 – .775 .320 – ...
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LT1170/LT1171/LT1172 PACKAGE DESCRIPTION .300 – .325 (7.620 – 8.255) .008 – .015 (0.203 – 0.381) +.035 .325 –.015 ( ) +0.889 8.255 –0.381 NOTE: 1. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR ...
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PACKAGE DESCRIPTION .060 .256 (1.524) (6.502) .060 .183 (1.524) (4.648) .075 (1.905) .300 (7.620) BOTTOM VIEW OF DD PAK HATCHED AREA IS SOLDER PLATED COPPER HEAT SINK .067 RECOMMENDED SOLDER PAD LAYOUT NOTE: 1. DIMENSIONS IN INCH/(MILLIMETER) 2. DRAWING NOT ...
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LT1170/LT1171/LT1172 PACKAGE DESCRIPTION .050 BSC .245 MIN .030 ±.005 TYP RECOMMENDED SOLDER PAD LAYOUT .010 – .020 (0.254 – 0.508) .008 – .010 (0.203 – 0.254) NOTE: 1. DIMENSIONS IN 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT ...
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PACKAGE DESCRIPTION .030 ±.005 TYP N .420 MIN RECOMMENDED SOLDER PAD LAYOUT .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 (0.254 – 0.737) .005 (0.127) RAD MIN .009 – .013 NOTE 3 (0.229 – ...
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LT1170/LT1171/LT1172 PACKAGE DESCRIPTION .390 – .415 (9.906 – 10.541) .230 – .270 (5.842 – 6.858) .460 – .500 (11.684 – 12.700) .330 – .370 (8.382 – 9.398) .067 BSC .028 – .038 (1.70) (0.711 – 0.965 Package 5-Lead ...
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... Updated to Reactivate LT1172M from Obsoleted Parts List 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Directly Regulates ±V OUT Low 1mA Quiescent Current Synchronizable 25V 1.25A Out from an SO-8 6W Output, ±5% Regulation, No Optocoupler Needed 1.5A Switch, Good for 5V to 3.3V Push-Pull, <100μV Output Noise P-P LT 0410 REV G • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 1991 117012fg ...