LT1304 Linear Technology Corporation, LT1304 Datasheet
LT1304
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LT1304 Summary of contents
Page 1
... Peak switch current, internally set at 1A, can be reduced by adding a single resistor from the I high speed operation of the LT1304 allows the use of small, surface-mountable inductors and capacitors. The LT1304 is available in an 8-lead SO package. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... LT1304/LT1304-3.3/LT1304 ABSOLUTE MAXIMUM V Voltage ................................................................ Voltage ............................................... – 0.4V to 25V FB Voltage (LT1304) ...................................... V Sense Voltage (LT1304-3.3/LT1304-5) ..................... 8V I Voltage .............................................................. 5V LIM SHDN Voltage ............................................................ 6V LBI Voltage ............................................................... V LBO Voltage ............................................................... 8V Maximum Power Dissipation ............................. 500mW Junction Temperature.......................................... 125 C Operating Temperature Range ..................... Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ...
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... SWITCH CURRENT (A) 1304 G01 Feedback Voltage 1.250 1.245 1.240 1.235 1.230 1.225 1.220 1.215 1.210 1.205 1.200 –50 – TEMPERATURE ( C) 1304 G04 LT1304/LT1304-3.3/LT1304 2V unless otherwise noted. IN SHDN CONDITIONS 700mA SW Switch Off Peak Switch Current Limit 1.3 1.2 1.1 1.0 0.9 0.8 ...
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... The low-battery detector remains active. The SHDN input should not be left floating. If SHDN is not used, tie the pin to V FB/SENSE (Pin 8): On the LT1304 (adjustable) this pin goes to the comparator input. On the fixed-output ver- sions, the pin connects to the resistor divider which sets output voltage ...
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... W BLOCK I D AGRA S LBI + 1 – 1.17V R3 FB – 1.24V V REF Figure 1. LT1304 Block Diagram. Independent Low-Battery Detector A3 Remains Alive When Device Is in Shutdown LBI 1 SENSE 8 590k 355k (LT1304-3.3), 195k (LT1304-5) LT1304/LT1304-3.3/LT1304 LB0 2 1.5V UNDERVOLTAGE LOCKOUT 36mV + A2 – A3 BIAS Q3 ~1V OFF TIMERS ...
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... For the majority of 2-cell or 3-cell input LT1304 applications inductor such as the Sumida CD54-220 (drum) or Coiltronics CTX20-1 (toroid) will suffice. If switch current is reduced using the I smaller inductors such as the Sumida CD43 series or Coilcraft DO1608 series can be used ...
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... DO3316, DO1608, DO3308 Capacitor Selection Low ESR (Equivalent Series Resistance) capacitors should be used at the output of the LT1304 to minimize output ripple voltage. High quality input bypassing is also re- quired. For surface mount applications AVX TPS series tantalum capacitors are recommended. These have been specifically designed for switch mode power supplies and have low ESR along with high surge current ratings ...
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... LT1304/LT1304-3.3/LT1304-5 U OPERATIO If the full power capability of the LT1304 is not required, peak switch current can be limited by connecting a resistor R from the I pin to ground. With R LIM LIM switch current is reduced to approximately 500mA. Smaller power components can then be used. The graph in Figure 6 shows switch current vs R resistor value ...
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... Figure 10 illustrates battery life vs load current of Figure 9’s LT1304, 2-cell to 5V DC/DC converter. Note the acceler- ated decrease in hours at higher power levels. Figure 11 plots total watt hours vs load current. Watt hours are ...
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... AA cell alkaline battery. U TYPICAL APPLICATIONS TM Super Burst Low I DC/DC Converter H** Q 200k 2N3906 47k V IN LBO + 2 CELLS 100 F LT1304 FB SHDN 47k * 1% METAL FILM ** SUMIDA CD54-330 10 100 Figure 12. Overall System Efficiency Including Battery Efficiency vs Load Current. Internal Impedance of Alkaline AA Cells ...
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... L1A † 16V LT1304-5 SENSE SHDN SHUTDOWN I LIM GND NC *COILTRONICS CTX20-1 **TOKIN 1E105ZY5U-C103-F † AVX TPSD476M016R0150 †† AVX TPSD107M010R0100 LT1304/LT1304-3.3/LT1304-5 MBRS130L SW 3.3V SENSE 300mA + C2** GND 100 F 10V 1304 TA05 C1 L1B* MBRS130L 3 3.3V 300mA †† 100 F 10V 1304 TA07 C1** ...
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... PROVIDED BY AN INDEPENDENT CIRCUIT **SUMIDA CD54-220 † AVX TPSD107M010R0100 12 † D1 1.07M 1% 12V 200mA + 124k 47 F** 1% 16V 1304 TA11 MBRS130LT3 22 H** (5V SENSE LIM + † LT1304CS8-5 100 F 10V LBI SHDN GND LBO 5V to 12V Converter Efficiency 300 1 10 100 LOAD CURRENT (mA) 1304 TA12 < 2. OUT ...
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... F 22k VOLTAGE ADJUST 1kHz PWM INPUT Electroluminescent Panel Driver with 200Hz Oscillator MUR160 1:12 MBR0530 SHDN 22k 51k LBO LT1304 1nF 50k LBI INTENSITY I ADJUST GND LIM 0. 200Hz CERAMIC –V OUT –14V TO –22V 1mA TO 10mA ** 10 F 1000pF ** 35V + EFFICIENCY = 70% TO 75% ...
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... GND * DALE LPE3325-A205 TRANSFORMER MEASURES 6.5mm 8.2mm 5.2mm (H) (605) 665-9301 ** IRC CGX-1/2 ALL 0.01 F CAPACITORS 250WVDC BAS21 OR MUR130 2- to 4-Cell to 5V Converter with Output Disconnect 2k L1** MBRS130L SENSE LT1304-5 + SHDN GND LIM SHUTDOWN NC 0.01 F 0. OUT 1kV 250 ...
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... Converter with Auxiliary 10V Output 1 F CERAMIC L1* MBRS130L SENSE LT1304-5 100 F SHDN I GND LIM SHUTDOWN NC 2-Cell to 5V Converter with Auxiliary – 5V Output L1 SENSE 1 F LT1304-5 100 F CERAMIC SHDN I GND LIM MBR0530 SHUTDOWN NC MBR0530 10V 20mA + 10 F MBR0530 5V 150mA + 100 F 1304 TA18 MBRS130L 5V 150mA + 100 F MBR0530 – ...
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... LT1304/LT1304-3.3/LT1304-5 PACKAGE DESCRIPTION 0.010 – 0.020 45 (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.016 – 0.050 0.406 – 1.270 * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" ...