LT1512CGN Linear Technology, LT1512CGN Datasheet
LT1512CGN
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LT1512CGN Summary of contents
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... Accuracy constant-voltage mode is perfect for lithium battery applications. Charging current can be easily programmed for all battery types. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. C2** D1 2.2μ ...
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LT1512 ABSOLUTE MAXIMUM RATINGS (Note 1) Input Voltage ........................................................... 30V Switch Voltage ......................................................... 40V S/S Pin Voltage ........................................................ 30V FB Pin Voltage (Transient, 10ms) ........................... ±10V V Pin Current ..................................................... 10mA FB Pin Voltage (Transient, 10ms) .......................... ±10V I FB ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T unless otherwise noted. SYMBOL PARAMETER V I Reference Voltage IREF FB I Input Current FB I Reference Voltage Line Regulation FB g Error Amplifi er Transconductance m Error Amplifi er ...
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LT1512 TYPICAL PERFORMANCE CHARACTERISTICS Switch Saturation Voltage vs Switch Current 1.0 150°C 0.9 100°C 25°C 0.8 0.7 0.6 0.5 –55°C 0.4 0.3 0.2 0 0.2 0.4 1.0 1.2 1.4 1.6 0.6 0.8 1.8 SWITCH CURRENT (A) 1512 G01 ...
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PIN FUNCTIONS I : The current feedback pin is used to sense charging FB current the input to a current sense amplifi er that controls charging current when the battery voltage is below the programmed voltage. During constant-current ...
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LT1512 OPERATION The LT1512 is a current mode switcher. This means that switch duty cycle is directly controlled by switch current rather than by output voltage or current. Referring to the Block Diagram, the switch is turned “on” at the ...
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APPLICATIONS INFORMATION CONNECT D2 ANODE HERE FOR FULLY CHARGED BATTERY VOLTAGE LESS THAN 3.5V. Q1 WILL NOT BE TURNED OFF IN SHUTDOWN IF V SHUTDOWN adequate drive to the transistor (even when the its lowest operating point ...
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LT1512 APPLICATIONS INFORMATION especially low. RMS ripple current in the input capacitor is less than 0.1A with L = 33μH and less than 0.2A with L = 15μH. A low ESR 22μF , 25V solid tantalum capacitor (AVX type TPS ...
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APPLICATIONS INFORMATION With I = 0.5A 15V and V CHRG IN BAT The recommended capacitor is a 2.2μF ceramic type from Marcon or Tokin. These capacitors have extremely low ESR and high ripple current ratings in a small ...
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... Very low duty cycle (<10 problem because the peak detector requires a fi nite up-time to reset C6. More Help Linear Technology Field Application Engineers have a CAD spreadsheet program for detailed calculations of circuit operating conditions, and our Applications Department is always ready to lend a helping hand. For additional informa- tion refer to the LT1372 data sheet. This part is identical to the LT1512 except for the current amplifi ...
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... MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 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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... Step-Down Charger that Allows Charging During Computer Operation and Prevents Wall-Adapter Overload Step-Up/Step-Down Charger for Current www.linear.com ● C2** D1 2.2μF MBRS130LT3 8 0. • 22μF 24Ω 25V C4 R3 0.22μF 0.2Ω 1512 F06 LT 0109 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2008 1512fa ...