LPM2100 bg NB Module Hardware Usage Guide
Shanghai Yuge Information Technology Co., Ltd.
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The SIM_DECT pin acts as an input detection pin to determine whether the SIM card is
inserted or not. The SIM_DECT pin defaults to a high level. The hot plug function can be
turned on or off by AT+HOSCFG. This function is disabled by default (see the
“
RDA_AT
Command Manual
”
provided in the domain for details).
=Table 3-9 SIM card hot swap detection pin definition
NO
Pin detection status
Functional description
1
High
SIM card insertion, SIM_DECT is high
2
Low
SIM card is pulled out, SIM_DECT is low
Figure 3-15 SIM card hot swap detection circuit*
①
It is recommended to add a diode protection next to the SIM_DECT pin of the
module.
②
When using a normally closed SIM card holder or a normally open SIM card holder,
the detection level can be set by the AT command. If AT+HOSCFG=1,1 is set, the state of the
SIM card is high when it is in position. When AT+HOSCFG=1,0 is set, the state of the SIM
card is low when it is in position. When AT+HOSCFG=0,0 is set. The SIM card hot plug
function is turned off.
③
"*" indicates that it is under development.
