Table of Contents
Advertisement
4.2.12 SIM INTERFACE
The SIM interface module within MTK6226 allows access to the subscriber identity module smart card.
With the appropriate software and level conversion by MT6305, the interface is compliant with GSM
11.11 and GSM 11.12.
The electrical interface consists of five signals:
SIMVCC
This output connects to contact C306 (VCC) of the SIM connector. It is used to supply power to the
SIM card and is supplied directly from MT6305.
It is controlled by MTK6226 , and enable the power and 3V operation respectively. Note that while
SIMPWR is low, the software sets SIMRST, SIMCLK and SIMDATA signals low.
SIMRST
This output connects to contact V502 (RST) of the SIM connector. It is set directly by the CPU writing
to the SIM control register.
SIMCLK
This output connects to contact V501 (CLK) of the SIM connector. The clock may be set high or low, or
a choice of 13/4 MHz or 13/12 MHz clock frequencies may be selected, by writing to the SIM control
register. In order to save power, the clock should be stopped when not required, if the SIM allows it.
SIMDATA
This is a bi-directional, open drain signal, connected to contact V504 (I/O) of the SIM connector.
Control of the data signal is done in the SIM interface section of MTK6226, although the output can be
disabled by writing to the SIM control register. Being opendrain with an external pull-up, the output
floats high when not being driven low by either Trident-HP or the SIM card.
All the above control signals maintain their state when MTK6226 is powered down. This allows the
SIM to remain powered during soft-OFF. SIMPWR should be switched OFF when handset °Æhard-
OFF' mode is selected.
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. Circuit Description
- 41 -
LGE Internal Use Only
Advertisement
Table of Contents
