Sim Detect Trouble Shooting - LG L240 Service Manual

4.8 SIM Detect Trouble Shooting

SIM interface scheme is shown below.
SIM_IO, SIM_CLK, SIM_RST ports are used to communicate DBB with ABB and the Charge Pump in
ABB enables 1.8V/3V SIM operation.
SIM CONNECTOR
VRSIM
1
VCC
2
SIM_RST RST
R218 24 3
SIM_CLK CLK
1-1705300-6
C206 C207
R219
C208
0.1u NA
150p 150p
<Fig.1> SIM Circuit Diagram
SIM_CLK : SIM Card reference clock
SIM_RST : SIM Card async/sync reset
SIM_IO : SIM Card bi-directional data line
z Connection between SIM and DBB
- SIM_CLK, SIM_IO, SIM_RST, SIM_PWRCTRL
z Check Points
- Contact between SIM and socket
- Soldering of SIM socket
z Trouble Shooting
- Insert the SIM into socket
- Connect PIF_UNION Jig to the phone, and Power on
z Trouble Shooting Procedure
- Check the power supply
- Check the soldering of SIM socket
- Check the SIM
R211 10K
4
GND SIM_PWRCTRL
5
VPP
6
I_O SIM_IO
J201
C209
22p
- 71 -
4. TROUBLE SHOOTING
C209
R211
C209 R218 C206
SIM_PWRCTRL : SIM Card power activation
SIM_RnW : SIM Card data line direction
SIM_CD : SIM Card presence detection
J201