SMB329/SMB339

Preliminary Information

© SUMMIT Microelectronics, Inc. 2004 • 757 N. Mary Avenue • Sunnyvale CA 94085 • Phone 408 523-1000 • FAX 408 523-1266

http://www.summitmicro.com/

2132 2.6 5/5/2009

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Programmable Switch-mode, Li+ Battery Chargers with TurboCharge™ Mode, USB “On-

the-Go” Power, USB Power Source Detection and Automatic Input Current Limiting

INTRODUCTION

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Automatic input current limit *

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Optional automatic power source detection per latest USB

charging specification 1.0

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USB or AC input with programmable input current limiting

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Up to 1.25A continuous charging current from AC adapter

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Up to 750mA charging current from 500mA USB port using

automatic TurboCharge™ mode *

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+4.35 to +6.2V input range (+18V input protected)

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USB “On-the-Go” Power support for USB OTG enabled

devices (+5V reverse output @ 500mA)

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50mA SYSON output for “dead battery” boot-up (SMB329)

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Analog output voltage for direct charge current measurement

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Reverse current blocking

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High-efficiency 3MHz current-mode step-down regulator

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Integrated frequency compensation and power MOSFETs

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High-accuracy float voltage regulation: 1%

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Pre-charge and complete-charge safety timers

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Battery pack thermal monitor

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Digital programming of all major parameters via I

(One-time programmable for default, non-volatile settings)

o

Fast charge voltage threshold, float voltage

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Pre-charge, fast charge, termination current

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Status register monitors and flags charger operation

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Charge in-progress/termination

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Charge timer fault

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Over-current limiting

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UV/OV detection/shutdown

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1.95mm x 2.22mm CSP-20 package (0.4mm pitch lead-free)

Applications

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2.5G/3G/GSM/CDMA Phones

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Smartphones/PDAs

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Portable Media Players

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Portable GPS Terminals

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Handheld Game Consoles

The SMB329 and SMB339 are programmable single-cell lithium-ion/lithium-

polymer battery chargers designed for a variety of portable applications.

The devices provide a simple and efficient way to charge high-capacity Li-

Ion batteries via a USB or AC adapter input. Furthermore, the SMB329 and

SMB339 are able to automatically adjust input current level by detecting the

AC/DC adapter’s maximum stable output current, thereby automatically

matching wall adapter to electronic device.

Unlike conventional devices, the SMB329’s and SMB339’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. A 50mA SYSON switch output

provides a bypass power supply to boot the system for “instant on” without

waiting for charging in case of a dead battery (SMB329 only). Both products

also support USB On-the-Go devices by providing the required USB-OTG

+5V power supply using the Li-Ion battery as a source.

The SMB329 and SMB339 can switch between USB mode and AC Adapter

mode and work seamlessly in conjunction with a USB controller.

Furthermore, they offer the option to automatically differentiate an AC/DC

wall adapter from a USB2.0 hub via the D+/D- USB lines, making them

compatible with USB battery charging specification 1.0.

Charge control includes qualification, trickle-charge, pre-charge, constant

current/constant voltage, float voltage and termination/safety settings that

are fully programmable via a serial I2C/SMBus, making the devices truly a

flexible solution. Fast charge current level can be set via I2C (limited in USB

mode to ensure 100mA or 500mA input). Built-in is reverse-current blocking

to prevent inadvertent cell discharge. The SMB329 and SMB339 offer the

option to automatically charge the battery only when the battery voltage is

below a selectable “dead-battery” threshold. High-frequency operation and

integrated power FETs contribute to a reduced external component count

and size.

The SMB329 and SMB339 also offer several features that protect the

battery pack as well as the charger and input circuitry: over-current,

under/over-voltage 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 SMB329 and SMB339

are available in an ultra-compact lead-free uCSP-20 package and are rated

over the –30C to +85C temperature range. The SMB329 is also offered in a

4x4 QFN-24 package.

SYSTEM APPLICATION

FEATURES & APPLICATIONS

Handheld System

USB

USB

USB

500mA

4.35V-5.5V

AC/DC

300-1800mA

4.5V-6.0V

I2C

System

SMB329

SMB339

Li-Ion

USB

Total Output

550-1250mA

To System

USB-OTG

Output 500mA

"Instant On" Power 50mA (SMB329)

ADC

Figure 1 – Using the SMB329/339 to charge a single cell Li+ battery from USB or AC Adapter power sources.

* Patents pending