Altec gsm socket al7024s Manuale Utente

AL7020S, AL7024S Designer’s Guide 

 

Doc. No. DG_7024E 

Altec Electronic AG  

Seite 19 / 32 

 
4 signals exist: 
 
• SIMVCC: SIM power supply. 
• SIMRST: reset. 
• SIMCLK: clock. 
• SIMDATA : I/O port. 
 
The SIM interface controls a 3V SIM. This interface is fully compliant with GSM 11.11 
recommendations concerning SIM functions. It is recommended to add Transient 
Voltage Suppressor diodes on the signal connected to the SIM socket in order to 
prevent any Electrostatic Discharge. TVS diodes with low capacitance (less than 
10pF) have to be connected on SIMCLK and SIMDATA to avoid any disturbance of 
the rising and falling edge. These types of diodes are mandatory for the Full Type 
Approval. They shall be placed as close as possible to the SIM socket. 

 

 

SIMCLK 32 O 2X 

SIM 

Clock 

SIMRST 31 O  2X 

SIM 

Reset 

SIMDATA 

30 

I/O 

CMOS / 3X 

SIM DATA 

SIMVCC 28 O    SIM 

Power 

Supply 

 

 

VCC 1 

SIMVCC 

RST 2 

SIMRST 

CLK 3 

SIMCLK 

CC4 

4 

VCC module (Not connected) 

GND 5 

GROUND 

VPP 6 

Not 

connected 

I/O 7  SIMDATA 
CC8 

8 

SIMPRES (Not connected) 

 

 

 
                  
 
 
 

 

 
 
 
 
 
 

1

2

3

4

5 

6 

7 

8 

SIMVCC 

SIMRST 

SIMCLK 

GND 

SIMDATA 

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