WH-LTE-7S1-E Hardware Manual
Technical Support:
Jinan USR IOT Technology Limited
www.pusr.com
10
WH-LTE-7S1-E has integrated SIM card function and can be used directly, users can also design according to
the needs with the SIM pins.
Recommendations:
1. In order to prevent the damage of USIM card and chip caused by static electricity, it is necessary to add
TVS tube for electrostatic protection. Please select devices with rated reverse working voltage VRWM
=5V and junction capacitance CJ < 10 pF. The reference ground of the antistatic device and the module
must be connected.
2. It is suggested to use VSIM power to pull up SIM_DATA 10K to ensure that SIM_DATA has a stable high
level in three states, so as to improve the driving ability and the edge characteristics of its waveform.
3. In order to meet the requirements of 3GPP TS 51.010-1 protocol and EMC certification, it is
recommended to place the SIM card holder close to the SIM card interface of the module to avoid
serious distortion of the waveform and influence of signal integrity due to too long wiring.
4. SIM_CLK and SIM_DAT should be protected by the ground.
5. Please parallel a capacitor of 0.1uF and 33pF between VSIM and GND, and a capacitor of 33pF between
SIM_CLK, SIM_RST, SIMA_DAT and GND to filter the interference of RF signals.
6. The ESD protection device should be placed close to the SIM card slot.
PIN
Symbol
Description
Type(V)
20
VSIM
SIM power
1.8/3.0
21
SIM_DAT
SIM data I/O
1.8/3.0
22
SIM_CLK
SIM clock I/O
1.8/3.0
23
SIM_RST
SIM reset I/O
1.8/3.0