SIM802 Hardware Design
The SIM interface is powered from an internal regulator in the module having normal voltage 3V.
All pins reset as outputs driving low. Logic levels are as described in table
Table 17: Signal of SIM interface
Signal
Pin
Description
SIM_VDD
9
SIM Card Power supply, it can identify automatically the SIM Card
power mode
,
one is 3.0V±10%, another is 1.8V±10%. Current is
about 10mA.
SIM_DATA
6
SIM Card data I/O
SIM_CLK
7
SIM Card Clock
SIM_RST
8
SIM Card Reset
,
it
's
best to connect PF cap to GND for ESD.
Notes: The SIM802 module default supports SIM card interfaces, but the SIM802 module
supports embedded SIM IC also, if the module has embedded SIM IC, SIM card interfaces keep
pins open.
Following is the reference circuit about SIM interface. We recommend an Electro-Static discharge
device ST (
) ESDA6V1W5 or ON SEMI (
ANTI”. The 22
Ω
resistors showed in the following figure should be added in series on the IO line
between the module and the SIM card for protecting the SIM I/O port. The pull up resistor (about
10K
Ω
) must be added on the SIM_DATA line. Note that the SIM peripheral circuit should be
placed close to the SIM card socket.
3.11.2 Design considerations for SIM card holder
The reference circuit about 6 pins SIM card illustrates as following figure.
SIM802_HD_V2.01
12.01.2010
51