SIM800L datasheet(39/73 Pages) SIMCOM

39 / 73 page

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Module

SIM Card

VCC

GND

RST

VPP

CLK

I/O

C707 10M 006 512 2

22pF

100nF

SIM_VDD

SIM_RST

SIM_CLK

SIM_DATA

SIM_DET

ESDA6V1

51Ω

Figure 34: Reference circuit of the 6-pin SIM card holder

4.8.2.

SIM Card Design Guide

SIM card signal could be interferenced by some high frequency signal, it is strongly recommended to follow

these guidelines while designing:

SIM card holder should be far away from GSM antenna

SIM traces should keep away from RF lines, VBAT and high-speed signal lines

The traces should be as short as possible

Keep SIM card holder’s GND connect to main ground directly

Shielding the SIM card signal by ground well

Recommended to place a 100nF capacitor on SIM_VDD line and keep close to the SIM card holder

Add some TVS which parasitic capacitance should not exceed 50pF

Add 51Ω resistor to (SIM_RST/SIM_CLK/SIM_DATA) signal could enhance ESD protection

4.8.3.

Design Considerations for SIM Card Holder

For 8 pins SIM card holder, SIMCom recommends to use Molex 91228.Customer can visit

http://www.molex.com for more information about the holder.

SIM800H&SIM800L_Hardware Design_V2.02

2015-07-27

SIM800L 데이터시트(PDF) 39 Page - SIMCom