Usim Card Reference Circuit - YUGE CLM920 TD3 Usage Manual

CLM920 TD3 LTE Module Hardware Usage Guide

3.7.1 USIM card reference circuit

The CLM920 TD3 module does not come with a USIM card slot. Users need to design a
USIM card slot on their own interface board. USIM card interface reference circuit is as
follows：
 It is recommended to select ONSEMI's SMF15C device for ESD protection on the SIM
interface line. The peripheral circuit device should be placed close to the card holder, and
the SIM card holder is close to the module layout.
 The USIM card circuit is susceptible to radio frequency interference and does not
recognize or drop the card. Therefore, the card slot should be placed as far as possible
from the RF radiation of the antenna. The card trace should be as far away as possible
from the RF, power supply and high-speed signal lines.
 The UIM_DATA has been internally pulled up to VDD_EXT through a 47K resistor, and
no external pull-up is required.
 UIM_DET is the USIM card insertion or non-insertion detection pin. It is high by default.
The SIM card status can be detected by this PIN pin during hot plug application.
 To avoid transient voltage overload, the USIM interface requires a 22R resistor in series
with each other on the signal line path.
 The ground of the USIM deck and the ground of the module should maintain good
connectivity.
Shanghai Yuge Information Technology co., LTD
reset VOL
Figure 3-16 USIM design circuit diagram
0 0 0.45
- 40 -