API9221

Car/Wall or USB Supply Input Lithium Battery Charger

with OVP USB Bypass and 10mA LDO

API9221

Document number: DS32204 Rev. 1 - 2

9 of 17

www.diodes.com

May 2010

© Diodes Incorporated

latched and is not re-set until one of the following events occurs:

2. The active supply is removed and re-applied

Note that the outputs, BAT, USB_BYP and VDC_LDO are reverse current protected. If an external voltage higher

than the supply voltage is connected to one of these outputs, that output will be disabled.

Charging from Adapter Power (VDC pin)

The battery can be charged from an AC powered wall adapter or in-car adapter at a current of up to 1.2A using

When VDC input is as recommended, (4.5V to 6.7V), no charge current is drawn from the VUSB input as VDC

takes precedence. Input operation below 4.5V is also possible, but the charging rate may be affected.

IVDC

R

6820

IVDC

=

Amp

For example, a resistor value of 13k

Ω sets a charge current of 0.525A. The recommended IVDC setting is 100mA

to 1200mA.

The maximum charge current available may be otherwise limited by the car/wall adapter current limit, by thermal

at the VDC input must be at least 4.8V to charge the battery to 4.2V in the minimum time.

The VDC input is safe from damage up to 28V.

Charging from USB Power (VUSB pin)

The battery can be charged at a current of up to 0.5A from this pin. In this case the maximum available charge

will begin to charge at a rate dependent on the battery voltage.

IUSB

R

6820

IUSB

=

Amp