4.14 RTC Trouble. LG KG291, KG290

4. TROUBLE SHOOTING

4.14 RTC Trouble

TEST POINT

R104

X100

Figure 24

CIRCUIT

MC-146_12_5PFX100

3

4

C121

NA

2 1

32.768KHz

_RD

_WR

_LBS

_UBS

BURSTCLK

_WAIT

ADV

C124

NA

C123 1000p

26M_DBB

_CHG_EN

_CHG_STAT

BT_LDO_EN

VIBRATOR

R103

_WR

_LBS

_UBS

0

B12

A17

A18

A11

A12

B11

W4

W3

B9

F2

F1

G4

G3

G2

RD

WE

LWR_LB

HWR_UB

BURSTCLK

WAIT

ADV

OSCIN

OSCOUT

CLKIN

GPIO_0

GPIO_1

GPIO_2

GPIO_3

GPIO_4

LGE Internal Use Only - 90 Copyright © 2007 LG Electronics. Inc. All right reserved.

Only for training and service purposes

4. TROUBLE SHOOTING

CHECKING FLOW

START

Is the voltage level at R104 about 1.2V

YES

Replace X100and try again.

YES

NO

RTC will work properly

Check the soldering of R104.

Copyright © 2007 LG Electronics. Inc. All right reserved.

Only for training and service purposes

- 91 LGE Internal Use Only