LG KT520 Service Manual page 68

3.5.3 Charging Part
The charging block in AB3000 processes the charging operation by using VBAT voltage. It is enabled
or disabled by the assertion/negation of the external signal DCIO. Part of the charging block are
activated and deactivated depending on the level of VBAT. (Fig.3-5-6) shows the schematic of
charging part.
BATT_GND
S2
DCIN_A
D2
D4
D3
D1
S1
SIA911DJ
Q600
When VBAT is below a certain value, 3.2V, a current generator take care of initial charging of the
CHSENSE+ node and internal trickle charge signal is active. This part of the charging block is
powered on and active when DCIO is asserted. The DCIO signal is asserted when its voltage is above
the voltage at VBAT. As soon as generator is turned off and all parts of the charging block are
functional and active.
Battery block indication as shown in (Fig.3-5-7)
4.17 ~3.67 (V)
100~40 (%)
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
VBAT
2012
R611
1%
0.1
1/4W
G2
R613 47K
G1
Fig. 3-5-6. Charging Part
3.67 ~3.52 (V)
40~12 (%)
Fig. 3-5-7 Battery Block Indication
- 69 -
3. TECHNICAL BRIEF
R610 0
route as a differential pair
DCIN
VBUS
3.52 ~3.4 (V) 3.4 ~3.2 (V)
12~3 (%) 3~0(%)
G11
FGSENSE-
H1
VBAT_D
E1
CHSENSE+
F2
CHSENSE-
E2
CHREG
F3
DCIO
J1
VBUS
LGE Internal Use Only