LTC3441 Linear Technology, LTC3441 Datasheet
LTC3441
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LTC3441 Summary of contents
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... The device is available in a 4mm 4mm 24-pin exposed-pad QFN package. , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. ...
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LTC3455 ABSOLUTE AXI U RATI GS (Note USB Voltages ...........................– 0. BAT MAX SW1, SW2 Voltages ....................– 0. TIMER Voltage ............................. – 0. PWRON, ON, ON2, ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are 0V unless otherwise noted. USB WALLFB PARAMETER CONDITIONS Battery-V PMOS MAX V PMOS Switch On-Resistance MAX V Switch Current Limit MAX V Switch Current Limit at ...
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LTC3455 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are 0V unless otherwise noted. USB WALLFB PARAMETER CONDITIONS Battery Charger Regulated Charger V Voltage BAT Charger Current Limit (USB Powered ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Feedback Pins (FB1, FB2) and AI Pin Voltage 815 810 AI 805 800 FB1 FB2 795 790 785 – 100 125 –25 0 TEMPERATURE ( C) 3455 G04 USB Pin ...
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LTC3455 W U TYPICAL PERFOR A CE CHARACTERISTICS Battery Charger Regulation Voltage 4.30 4.25 4.20 4.15 4.10 4.05 4.00 – 100 –25 0 TEMPERATURE ( C) 3455 G13 Charge Current When Wall-Powered 600 500 400 THERMAL CONTROL ...
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CTIO S FB1 (Pin 1): Feedback Pin for Switcher 1. Set the output voltage by connecting feedback resistors to this pin. PROG (Pin 2): Charge Current Program and Charge Cur- rent Monitor Pin. Connect a ...
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LTC3455 CTIO S FB2 (Pin 18): Feedback Pin for Switcher 2. Set the output voltage by connecting feedback resistors to this pin. ON2 (Pin 19): Enable Pin for Switcher 2. This pin turns on Switcher ...
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W BLOCK DIAGRA USB POWER MANAGER USB USB 4.7 F – REF + SUSPEND 6 USB CONTROLLER USBHP 5 1k CHRG V 4 MAX TIMER 3 PROG 2 0.1 F 2.49k GND BAT BAT ...
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LTC3455 U OPERATIO The LTC3455 is designed complete power manage- ment solution for a wide variety of portable systems. The device incorporates two current mode step-down switch- ing regulators, a full-featured battery charger, a USB power controller, ...
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U U APPLICATIO S I FOR ATIO Operation When No Battery Is Present As long as USB or wall power is available, the LTC3455 will operate with no battery present, a crucial requirement for systems with a removable battery. Keep ...
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LTC3455 U U APPLICATIO S I FOR ATIO Operation in USB Low Power Mode Most applications that draw power from the USB bus should be in low power mode only for a brief amount of time. All devices must be ...
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U U APPLICATIO S I FOR ATIO ceramic capacitance may be connected to the V without difficulty. More than 50 F requires using a capaci- tor with some ESR or adding some resistance in series with some of the ceramic ...
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LTC3455 U U APPLICATIO S I FOR ATIO ON2 19 23 PBSTAT PWRON V 9 BAT WALLFB 11 USB 8 SUSPEND 6 Startup and Shutdown When USB or Wall Powered Whenever USB or wall power is present ...
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U U APPLICATIO S I FOR ATIO Low or Bad Battery Protection (200ms Timeout) The 200ms reset timer is also used to prevent starting the LTC3455 when there is insufficient external power or insufficient battery voltage to regulate the outputs. ...
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LTC3455 U U APPLICATIO S I FOR ATIO Switching Regulator Inductor Selection Many different sizes and shapes of inductors are available from numerous manufacturers. Choosing the right induc- tor from such a large selection of devices can be over- whelming, ...
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... R2 able, even if the MODE pin is pulled high. Figure 8 shows the switching waveforms for switcher 1 R1 (both PWM mode and Burst Mode Operation) with V 3.6V, V OUT1 3455 F06 Burst Mode is a registered trademark of Linear Technology Corporation. LTC3455 100 Burst Mode 3. 1.8V 3.3V ...
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LTC3455 U U APPLICATIO S I FOR ATIO Burst Mode V SW1 2V/DIV V OUT1 50mV/DIV AC COUPLED I L1 100mA/DIV 5 s/DIV PWM Mode V SW1 2V/DIV V OUT1 10mV/DIV AC COUPLED I L1 100mA/DIV 1 s/DIV Figure 8. ...
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U U APPLICATIO S I FOR ATIO Charge and Recharge Cycles When external power is first applied, a new charge cycle is always initiated. The battery will continue charging until the programmed charge time is reached. If the battery voltage ...
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LTC3455 U U APPLICATIO S I FOR ATIO Battery Charger Thermal Limit An internal thermal limit reduces the charge current if the die temperature attempts to rise above approximately 105 C. This protects the LTC3455 from excessive tem- perature, and ...
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U U APPLICATIO S I FOR ATIO Hot Swap Output A current limited Hot Swap output is provided for power- ing memory cards or other external devices that can be hot-plugged into the system. Typically connected to the 3.3V supply, ...
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LTC3455 U TYPICAL APPLICATIO MODE USB 5V USB HSON SUSPEND USB 19 C6 ON2 5 CONTROLLER 4.7 F USBHP 22 PWRON 20 RST MAX PBSTAT LTC3455 4 24 ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 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 ...
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... Synchronous Step-Down OUT DC/DC Converter LTC3412 2. 4MHz, Synchronous Step-Down OUT DC/DC Converter LTC3414 4MHz, Synchronous Step-Down OUT DC/DC Converter LTC3440/LTC3441 600mA/ 2MHz/1MHz, Synchronous Buck-Boost OUT DC/DC Converter Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 8 USB MODE 6 HSON ...