Specifications

L506 Hardware Design
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3.5.2 Design Guide
USIM electronic characteristics as the table 3-8,3-9 show.
In order to meet the 3 GPP TS 51.010 1 protocol and EMC certification requirements. Suggest USIM
slot near the location of the module USIM card interface, to avoid running for too long, lead to serious
deformation of waveform and effect signal integrity, USIM_CLK and USIM_DATA signal lines
suggest ground protect. Between the USIM VCC & GND add a 1uF and a 33 pF capacitor in parallel,
Between the USIM_CLK& GND, USIM_RST& GND, USIM DATA& GND add a 33 pF capacitor in
parallel, for filter the RF signal interference.
3.5.3 USIM interface reference circuit
VCC
R8
C2
RST
CLK
DATA
DETECT
R9
R10
R11
C3 C4
VPP
USIM_VDD
USIM_RST
USIM_DATA
USIM_DET
USIM_CLK
C5 C6
22R
22R
22R
22R
NCNCNC
ESD
1UF 33PF
MODULE
SIM
GND
Figure 3-6 USIM Reference circuit
Note:1.USIM_DATA have added the pull-up resistance in the module design.
2. L506 support hot-plug detect, if need the function, please add this pin.