MIC79050_05 Datasheet, PDF (1/14 Pages) Micrel Semiconductor – Simple Lithium-Ion Battery Charger

MIC79050
MIC79050
Micrel, Inc.
Simple Lithium-Ion Battery Charger
General Description
The MIC79050 is a simple single-cell lithium-ion battery char-
ger. It includes an on-chip pass transistor for high precision
charging. Featuring ultrahigh precision (+0.75% over the Li-
ion battery charging temperature range) and “zero” off mode
current, the MIC79050 provides a very simple, cost effective
solution for charging lithium-ion battery.
Other features of the MIC79050 include current limit and
thermal shutdown protection. In the event the input voltage
to the charger is disconnected, the MIC79050 also provides
minimal reverse-current and reversed-battery protection.
The MIC79050 is a fixed 4.2V device and comes in the ther-
mally-enhanced MSO-8, SO-8, and SOT-223 packages. The
8-pin versions also come equipped with enable and feedback
inputs. All versions are specified over the temperature range
of –40°C to +125°C.
Features
• High accuracy charge voltage:
±0.75% over -5°C to + 60°C (Li-ion charging
temperature range)
• “Zero” off-mode current
• 10µA reverse leakage
• Ultralow 380mV dropout at 500mA
• Wide input voltage range
• Logic controlled enable input (8-pin devices only)
• Thermal shutdown and current limit protection
• Power MSOP-8, Power SOIC-8, and SOT-223
• Pulse charging capability
Applications
• Li-ion battery charger
• Celluar phones
• Palmtop computers
• PDAs
• Self charging battery packs
Ordering Information
Part Number
Standard
Pb-Free
MIC79050-4.2BS
MIC79050-4.2YS
MIC79050-4.2BM
MIC79050-4.2YM
MIC79050-4.2BMM MIC79050-4.2YMM
Voltage
4.2V
4.2V
4.2V
Junction
Temp. Range
–40ºC to +125ºC
–40ºC to +125ºC
–40ºC to +125ºC
Package
SOT-223-3
SOIC-8
MSOP-8
Typical Applications
Regulated or
unregulated
wall adapter
MIC79050-4.2BS
IN BAT
GND
4.2V 0.75% Over Temp
Li-Ion
Cell
Simplest Battery Charging Solution
Regulated or
unregulated
wall adapter
MIC79050-4.2BMM
IN BAT
EN FB
GND
4.2V 0.75%
Li-Ion
Cell
External PWM*
*See Applications Information
Pulse-Charging Application
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
August 2005
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MIC79050