
5G Module Series
RM502Q-GL Hardware Design
RM502Q-GL_Hardware_Design 31 / 77
Module
(U)SIM Card
Connector
USIM1_DET
USIM1_DATA
USIM1_CLK
RST
CLK
CD
IO
USIM1_VDD
USIM1_VDD
USIM1_RST
VCC
GND
VPP
GND
TVS
Note:
All these resistors, capacitors and TVS should be close to (U)SIM card connector in PCB layout.
36
30
32
66
34
10-20k
22R
22R
22R
3
3
p
F
3
3
p
F
3
3
p
F
100 nF
Figure 17: Reference Circuit of Normally Closed (U)SIM Card Connector
Normally Closed (U)SIM Card Connector:
⚫
When the (U)SIM is absent, CD is short-circuited to ground and USIM_DET is at low level.
⚫
When the (U)SIM is inserted, CD is open from ground and USIM_DET is at high level.
The following figure shows a reference design of (U)SIM interface with a normally open (NO) (U)SIM card
connector.
Module
(U)SIM Card
Connector
USIM1_DET
USIM1_DATA
USIM1_CLK
RST
CLK
CD1
IO
USIM1_VDD
USIM1_VDD
USIM1_RST
VCC
GND
VPP
GND
TVS
Note:
All these resistors, capacitors and TVS should be close to (U)SIM card connector in PCB layout.
36
30
32
66
34
10-20k
22R
22R
22R
3
3
p
F
3
3
p
F
3
3
p
F
100 nF
33k
1.8V
4.7k
CD2
Figure 18: Reference Circuit of Normally Open (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 level.
⚫
When the (U)SIM is inserted, CD1 is short-circuited to 1.8 V and USIM_DET is at high level.