SMB138/A/C Programmable Switch-mode, USB/AC Input Li+ Battery Charger with TurboCharge™ Mode and USB “On- the-Go” Power FEATURES & APPLICATIONS INTRODUCTION • • • • • • • • • • • • • • The SMB138 is a programmable single-cell lithium-ion/lithium-polymer battery charger designed for a variety of portable applications. The device provides a simple and efficient way to charge high-capacity LiIon batteries via a USB or AC adapter input. Unlike conventional devices, the SMB138’s high-efficiency, switch-mode operation eliminates the thermal problems of conventional linear solutions. Also the buck converter architecture effectively multiplies the input current to increase charge rate for the Li+ cell and uses current limited supplies like USB more efficiently. The SMB138 also supports USB On-the-Go devices by providing the required USB-OTG +5V power supply using the Li-Ion battery as a source. USB or AC input with programmable input current limiting Up to 1.25A continuous charging current from AC adapter Up to 750mA charging current from 500mA USB port using automatic TurboCharge™ mode +4.35 to +6.2V input voltage range (+16V tolerant) Two product options: 2 o SMB138A: charger off until I C command initiation, 2 enable/disable control via I C o SMB138C: charger powers up in charging mode, 2 enable/disable control via I C USB “On-the-Go” Power support for USB OTG enabled devices (+5V reverse output @ 200mA) Reverse current blocking (<5uA) High-efficiency 3MHz voltage-mode step-down regulator Integrated frequency compensation Internal power MOSFETs and precision current sensing High-accuracy float voltage regulation: 1% Thermal regulation (current foldback) Trickle charging Pre-charge and complete-charge (36/240min) safety timers 2 Digital programming of all major parameters via I C interface o Fast charge voltage threshold, float voltage o Pre-charge, fast charge, termination current Status register monitors and flags charger operation o Charge in-progress/termination o Charge timer fault o OC/UV/OV detection/shutdown uCSP-19 lead-free package (0.4mm ball pitch) The SMB138 can switch between USB mode and AC Adapter mode and works seamlessly in conjunction with a USB controller. Charge control includes qualification, trickle-charge, pre-charge, constant current/constant voltage, float voltage and termination/safety settings 2 that are fully programmable via a serial I C/SMBus and stored in nonvolatile memory making the device truly a flexible solution. Fast 2 charge current level can be set via I C (limited in USB mode to ensure 100mA or 500mA input). Built-in is reverse-current blocking to prevent inadvertent cell discharge. High frequency operation and integrated power FETs contribute to reduced external component count and size. CONFIDENTIAL DO NOT COPY 2 The SMB138A device requires a user I C command for charging initiation, whereas the SMB138C device powers up in the charging mode. The SMB138C offers the option to automatically charge the battery only when the battery voltage is below a selectable “deadbattery” threshold. The SMB138 also offers several features that protect the battery pack as well as the charger and input circuitry: over-current, under/overvoltage and thermal protection. Ultra-accurate, 1% battery float voltage control improves battery capacity utilization. The STAT output is an interrupt to flag various status/flag events (programmable selection) and the status register can be read via the serial port. The SMB138 is available in an ultra-compact lead-free uCSP-19 package and is rated over the –30C to +85C temperature range. Applications • • • • 2.5/3/3G+ GSM/CDMA/WCDMA Phones Smartphones/PDAs Portable Media Players Portable GPS Terminals SYSTEM APPLICATION USB 500mA 4.35V-5.5V USB-OTG Output 500mA VB US D- USB Handheld System D+ SMB138 NC GND USB Total Output 550-1250mA To system Li-Ion Charging • • • I2C System USB AC/DC 300-1800mA 4.5V-6.2V Figure 1 – Using the SMB138 to charge a single cell Li+ battery from USB or AC Adapter power sources © SUMMIT Microelectronics, Inc. 2004 • 757 N. Mary Avenue • Sunnyvale CA 94085 • Phone 408 523-1000 • FAX 408 523-1266 http://www.summitmicro.com/ 3.0 4/5/2008 1 SMB138/A/C PART MARKING Summit Part Number Lead-free Ball A1 Identifier Status Tracking Code (Summit Use) 138VSS 01AYWW Date Code (YWW) Multiple Lot Disignator X is the sequential number per wafer (1 for first wafer, 2 for second wafer, etc.) Drawing not to scale ORDERING INFORMATION Summit Part-Number SMB138 A Blank = see CSIR A = Power-off until I2C command C = Power-up in charge mode E nnn Y Lead Free Part Number Suffix Package Specific requirements are contained in the suffix E = 19-Ball Ultra CSPTM NOTICE SUMMIT Microelectronics, Inc. reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. SUMMIT Microelectronics, Inc. assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained herein reflect representative operating parameters, and may vary depending upon a user’s specific application. While the information in this publication has been carefully checked, SUMMIT Microelectronics, Inc. shall not be liable for any damages arising as a result of any error or omission. SUMMIT Microelectronics, Inc. does not recommend the use of any of its products in life support or aviation applications where the failure or malfunction of the product can reasonably be expected to cause any failure of either system or to significantly affect their safety or effectiveness. Products are not authorized for use in such applications unless SUMMIT Microelectronics, Inc. receives written assurances, to its satisfaction, that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; and (c) potential liability of SUMMIT Microelectronics, Inc. is adequately protected under the circumstances. Revision 3.0 - This document supersedes all previous versions. Please check the Summit Microelectronics Inc. web site at www.summitmicro.com for data sheet updates. © Copyright 2006 SUMMIT MICROELECTRONICS, Inc. PROGRAMMABLE POWER FOR A GREEN PLANET™ I2C is a trademark of Philips Corporation Summit Microelectronics, Inc 3.0 4/5/2008 2