Only For Training And Service Purposes - LG KP235 Service Manual

3. TECHNICAL BRIEF
D. SIM interface
The AD6721 provides SIM Interface Module. The AD6721 checks status periodically during
established call mode whether SIM card is inserted or not, but it doesn't check during deep Sleep
mode. In order to communicate with SIM card, 3 signals SIM_DATA, SIM_CLK,
SIM_RST(GPIO_23) are required. The descriptions about the signals are given by bellow Table 3-5
in detail.
Signals
SIM_DATA
SIM_CLK
SIM_RST
(GPIO_23)
SIM_DATA
LGE Internal Use Only
This pin receives and sends data to SIM card.
This model can support 3.0 volt and 1.8 volt interface SIM card.
Clock 3.25MHz frequency.
Reset SIM block
Table 3.5.D SIM CONTROL SIGNALS DESCRIPTION
2V85_VSIM
R337
15K
R338
0
C317
NA
Figure 3.5.D2 SIM Interface of AD6724
Description
2V85_VSIM
J300
4 1
C5 C1
5 2
C6 C2
6 3
C7 C3
10 7
GND4 GND1
9 8
GND3 GND2
C318
220n
Copyright © 2008 LG Electronics. Inc. All right reserved.
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SIM_RST
SIM_CLK
C319 C320
NA 1000p

Only for training and service purposes