LG KE520 Service Manual page 115

4. TROUBLE SHOOTING
4.22.1 Checking BT Antenna
4.22.1.1 Visual Inspection
<Fig. 1>
4.22.1.2 Checking VRIO and VBAT
Checking
VRIO and VBAT
Check R500, R501 1.8V
Check R502, R503 VBAT
YES
Check SYS_CLK_REQ
LGE Internal Use Only
NO
Check ABB
VBAT
- 116 -
VRIO VRIO
R500 R501
0 0
C502 C503
WLAN_SYSCLK
CLK_32K
2.2u 2.2u
WLAN_IRQ
WLAN_DEBUG_RX
R505
WLAN_DEBUG_TX
10K
SDIO_D1
SDIO_D2
SDIO_CMD
SDIO_CLK
SDIO_D3
SDIO_D0
SYS_CLK_REQ
MCSI1_DOUT
MCSI1_DIN
MCSI1_SYNC
MCSI1_BCLK
RWFS-T001A
48
GND16
47
GND15
46
GND14
45
GND13
44
R502
R503
R501
R500
<Fig. 2>
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
C500
47u
U500
1
VSW
2
VFB
3
VDDIO
4
VDDHOSTIF
5
GND1
C504 220p
6
CLK_IP
R504 0
7
SLEEP_CLK
TP501 8
WLAN_IRQ
9
HOSTIF_LVL_
10
RS232_RX
11
GND2
12
RS232_TX
TP502 13
SDIO_D1
TP503 14
SDIO_D2
TP505 15
SPI_DIN_SDIO
TP507 16
SPI_CLK_SDI
TP508 17
SPI_CSX_SDI
TP509 18
SPI_DOUT_SD
19
EXT_CLK_RE
20
GND3
TP510 21
AUD_IN
TP511 22
AUD_OUT
TP512 23
AUD_FSYNC
24
TP513
AUD_CLK
VBAT
2.2u C501
1.8V