LTC3577-3/LTC3577-4 Highly Integrated Portable Product PMIC Fea T Descrip T n The LTC 3577-3/LTC3577-4 are highly integrated power Full Featured Li-Ion/Polymer Charger/PowerPath management ICs for single cell Li-Ion/Polymer battery ap- Controller with Instant-On Operation n plications. It includes a PowerPath manager with automatic Triple Adjustable High Efficiency Step-Down load prioritization, a battery charger, an ideal diode, input Switching Regulators (800mA, 500mA, 500mA I ) OUT 2 n overvoltage protection and numerous other internal pro- I C Adjustable SW Slew Rates for EMI Reduction n tection features. The LTC3577-3/LTC3577-4 are designed High Temperature Battery Voltage Reduction to accurately charge from current limited supplies such as Improves Safety and Reliability n USB by automatically reducing charge current such that Overvoltage Protection Controller for USB (V )/Wall BUS the sum of the load current and the charge current does Inputs Provide Protection to 30V n not exceed the programmed input current limit (100mA Integrated 40V Series LED Back Light Driver with 60dB 2 or 500mA modes). The LTC3577-3/LTC3577-4 reduce the Brightness Control and Gradation via I C n battery voltage at elevated temperatures to improve safety 1.5A Maximum Charge Current with Thermal Limiting n and reliability. The three step-down switching regulators Battery Float Voltage: 4.2V (LTC3577-3) and two LDOs provide a wide range of available supplies. 4.1V (LTC3577-4) n The LTC3577-3/LTC3577-4 also include a pushbutton Pushbutton ON/OFF Control with System Reset n input to control power sequencing and system reset. The Dual 150mA Current Limited LDOs n onboard LED backlight boost circuitry can drive up to 10 Start-Up Timing Compatible with SiRF Atlas IV series LEDs and includes versatile digital dimming via the Processor 2 n I C input. The LTC3577-3/LTC3577-4 are designed to sup- Small 4mm 7mm 44-Pin QFN Package port the SiRF Atlas IV processor and has pushbutton timing and sequencing different from other LTC3577 versions. a T The LTC3577-3/LTC3577-4 are available in a low profile n PNDs, DMB/DVB-H, Digital/Satellite Radio, 4mm 7mm 0.75mm 44-pin QFN package. Media Players L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Hot n Portable Industrial/Medical Products Swap and PowerPath are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6522118, 6700364, n Other USB-Based Handheld Products 7511390, 5481178, 6580258. Other patents pending. Typical a T 5V LED Driver Efficiency (10 LEDs) ADAPTER OPTIONAL 90 100mA/500mA USB 1000mA 80 V OUT 70 0V OVERVOLTAGE 60 PROTECTION CC/CV MAX PWM CONSTANT CHARGER + SINGLE CELL 50 CURRENT CHARGE NTC Li-Ion LTC3577-3/LTC3577-4 40 2 0.8V to 3.6V/150mA DUAL LDO 2 I C PORT 30 REGULATORS 0.8V to 3.6V/150mA 20 LED BACKLIGHT WITH DIGITALLY 4 TO 10 LED CONTROLLED DIMMING BOOST 10 TRIPLE HIGH 0.8V to 3.6V/800mA EFFICIENCY 0 PUSHBUTTON PB 0.001 0.01 0.1 1 10 100 STEP-DOWN 0.8V to 3.6V/500mA CONTROL SWITCHING LED CURRENT (mA) 0.8V to 3.6V/500mA REGULATORS 357734 TA01b 357734 TA01a 357734fc 1 For more information www.linear.com/LTC3577-3 EFFICIENCY (%) ion pplica ions pplica ion uresLTC3577-3/LTC3577-4 Table o F c T Ts Table o F c T Ts Features ............................................................................................................................ 1 Applications ....................................................................................................................... 1 Typical Application ............................................................................................................... 1 Description......................................................................................................................... 1 Absolute Maximum Ratings ..................................................................................................... 3 Order Information ................................................................................................................. 3 Pin Configuration ................................................................................................................. 3 Electrical Characteristics ........................................................................................................ 4 Typical Performance Characteristics .........................................................................................10 Pin Functions .....................................................................................................................16 Block Diagram ....................................................................................................................19 Operation..........................................................................................................................20 PowerPath OPERATION ........................................................................................................................................ 20 Low Dropout Linear Regulator Operation ............................................................................................................. 28 Step-Down Switching Regulator Operation ........................................................................................................... 29 LED Backlight/Boost Operation ............................................................................................................................. 33 2 I C Operation ........................................................................................................................................................ 37 Pushbutton Interface Operation ............................................................................................................................ 42 Layout and Thermal Considerations ..................................................................................................................... 46 Typical Applications .............................................................................................................48 Package Description ............................................................................................................50 Revision History .................................................................................................................51 Related Parts .....................................................................................................................52 357734fc 2 For more information www.linear.com/LTC3577-3 en on en on