Charging Circuit - LG KM380t Service Manual

3.16 Charging circuit

ISL9221 accepts two power inputs, normally one from a USB (Universal Serial Bus) port and the other
from a desktop cradle.
The ISL9221 features 28V and 7V maximum voltages for the cradle and the USB inputs respectively.
Due to the 28V rating for the cradle input, low-cost, large output tolerance adapters can be used
safely. An over voltage protection functions are integrated in ISL9221 for USB & Charge
VIO_2V62
EOC
TP515
CHG_EN
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
OVP CHARGING IC
VCHG
VBUS_USB
U303
1
VDC
2
VUSB
3
_PPR
4
_CHG
5
_EN
6
IMIN
(1%)
Figure 22. Charging Circuit Diagram
- 49 -
3. TECHNICAL BRIEF
VBAT
ISL9221
13
PGND
12
VDC_BYP
11
BAT
10
USB_BYP
9
IVDC
8
GND
7
IUSB
R319
R596 16K
(1%)
DNI
VCHG_OVP VBUS_OVP
C332 C333 C334
0.1uF 0.1u 0.1u
LGE Internal Use Only