Sim Detect Trouble Shooting - LG KE520 Service Manual

4. TROUBLE SHOOTING

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.
R628 24
SIM_CLK
SIM_RST
C615 C616
150p 150p
SIM_CLK : SIM Card reference clock
SIM_RST : SIM Card async/sync reset
LGE Internal Use Only
VRSIM
GND2 GND3
8
GND1 GND4
7
C3 C7
3
C2 C6
2
C1 C5
1
J600
C617
0.1u
<Fig.1> SIM Circuit Diagram
C618
R628
C615
- 88 -
R627
9
10
6
5
4
C618
22p
(R628)
SIM_CLK
(C615)
SIM_RST
SIM_IO
(C618)
SIM_PWRCTRL : SIM Card power activation
SIM_IO : SIM Card bi-directional data line
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
10K
SIM_PWRCTRL
SIM_IO