Uim Card Interface; Figure 2-15 Reference Design Of Sim Card Interface - Neoway N720 Hardware User's Manual

N720 Hardware User Guide

2.5 UIM Card Interface

Name Pin No.
VUIM 35
UIM_DATA 36
UIM_CLK 37
UIM_RESET 38
UIM_DETECT 39
N720 supports 1.8 V/3 V UIM cards. VUIM is the power supply pin of the UIM card and its maximum
load is 30 mA. The UIM_DATA pin is not pulled up internally, so reserve a pull-up resistor externally in
design. UIM_CLK is the clock signal pin, supporting 3.25 GHz of clock frequency. Figure 2-15 shows the
reference design of the UIM card interface.
UIM_DATA
UIM_CLK
UIM_RST
VUIM
UIM_DETECT
N720
ESD protectors, such as ESD diodes or ESD varistors (with a junction capacitance of less than 33 pF), are
recommended to be added on the SIM signals, especially in automotive or other applications with bad
ESD. Replace the ESD diodes with 27 pF to 33 pF capacitors connecting to GND in common applications.
The ESD diodes or small capacitors should be close to UIM card.
N720 supports SIM card detection. UIM_DETECT is 1.8 V interrupt pins. Low level means UIM card
detected while high level mean no UIM card detected.
Copyright © Neoway Technology Co., Ltd
I/O Function
PO UIM power supply
IO UIM data
DO UIM clock
DO UIM reset
DI UIM detect

Figure 2-15 Reference design of SIM card interface

Remarks
Compatible with 1.8 V/3 V UIM card
A 10 kΩ resistor is required between
VUIM and UIM-DATA.
A pull-up resistor is recommended
10
KΩ
UIM card
DATA
CLK
RST
VCC
SIM-Det
VDDIO_1P8
47
KΩ
1 uF
VPP
GND
GND
22