SMB329/SMB339
Programmable Switch-mode, Li+ Battery Chargers with TurboCharge™ Mode, USB “On-
the-Go” Power, USB Power Source Detection and Automatic Input Current Limiting
FEATURES & APPLICATIONS
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Automatic input current limit *
Optional automatic power source detection per latest USB
charging specification 1.0
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 range (+18V input protected)
USB “On-the-Go” Power support for USB OTG enabled
devices (+5V reverse output @ 500mA)
50mA SYSON output for “dead battery” boot-up (SMB329)
Analog output voltage for direct charge current measurement
Reverse current blocking
High-efficiency 3MHz current-mode step-down regulator
Integrated frequency compensation and power MOSFETs
High-accuracy float voltage regulation: 1%
Pre-charge and complete-charge safety timers
Battery pack thermal monitor
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Digital programming of all major parameters via I C interface
(One-time programmable for default, non-volatile settings)
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Fast charge voltage threshold, float voltage
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Pre-charge, fast charge, termination current
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
1.95mm x 2.22mm CSP-20 package (0.4mm pitch lead-free)
Preliminary Information
INTRODUCTION
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.
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Applications
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2.5G/3G/GSM/CDMA Phones
Smartphones/PDAs
Portable Media Players
Portable GPS Terminals
Handheld Game Consoles
* Patents pending
SYSTEM APPLICATION
USB
500mA
4.35V-5.5V
VB US D-
Handheld System
"Instant On" Power 50mA (SMB329)
USB-OTG
Output 500mA
Total Output
550-1250mA
Charging
To System
USB
USB
SMB329
SMB339
Li-Ion
System
AC/DC
300-1800mA
4.5V-6.0V
Figure 1 – Using the SMB329/339 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/
2132 2.6 5/5/2009
D+
NC GND
ADC
I2C
USB
1
SUMMIT [ SUMMIT MICROELECTRONICS, INC. ]
