Quectel RM500Q-AE Manual page 35

Module
USIM_VDD
USIM_RST
USIM_CLK
USIM_DET
USIM_DATA
GND
Note: All these resistors, capacitors and TVS should be close to (U)SIM card connector in PCB layout.
Figure 13: Reference Circuit for Normally Closed (U)SIM Card Connector
Normally Open (U)SIM Card Connector:
⚫
When the (U)SIM is absent, CD1 is open from CD2 and USIM_DET is at low voltage level.
⚫
When the (U)SIM is inserted, CD1 is short-circuited to 1.8 V and USIM_DET is at high voltage level.
The following figure shows a reference design of (U)SIM interface with a normally open (NO) (U)SIM card
connector.
Module
USIM_VDD
USIM_RST
USIM_CLK
USIM_DET
USIM_DATA
GND
Note: All these resistors, capacitors and TVS should be close to (U)SIM card connector in PCB layout.
Figure 14: Reference Circuit for Normally Open (U)SIM Card Connector
If (U)SIM card detection function is not needed, please keep USIM_DET disconnected. A reference circuit
for (U)SIM card interface with a 6-pin (U)SIM card connector is illustrated by the following figure.
RM500Q-AE&RM502Q-AE_Hardware_Design
USIM_VDD
10-20k
22R
22R
22R
USIM_VDD
10-20k
22R
22R
22R
RM500Q-AE&RM502Q-AE Hardware Design
100 nF
VCC
RST
CLK
CD
IO
GND
TVS
(U)SIM Card
100 nF
VCC
RST
CLK
CD1
IO
GND
33k
TVS
5G Module Series
(U)SIM Card
Connector
VPP
Connector
VPP
1.8 V
4.7k
CD2
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