Neoway N58 - Figure 5-23 Reference Design of USIM Card (with the Hot Plug Function) Interfaces

N58 Hardware User Guide
Chapter 5 Application Interfaces
Copyright © Neoway Technology Co., Ltd. All rights reserved.
47
USIM2_DATA
22
B
USIM2 data
input/output
Connect this pin to USIM2_VCC by
using a 4.7 kΩ pull-up resistor.
USIM2_CLK
23
DO
USIM2 clock output
-
USIM2_RESET
24
DO
USIM2 reset
-
USIM2_DET
25
DI
USIM2 detection
-
N58 provides two USIM card interfaces and supports dual USIM single standby. USIM1 is used by
default. Adaptive 1.8 V/3 V USIM cards are used. Figure 5-23 shows the reference design of USIM
card (with the hot plug function) interfaces.
Figure 5-23 Reference design of USIM card (with the hot plug function) interfaces
1uF
CLK
RST
VCC
VPP
GND
USIM Card
DATA
GND
DET
47kΩ
VDD_1P8
USIM_DATA
USIM_CLK
USIM_RESET
USIM_VCC
USIM_DET
N58 Module
4.7kΩ
C1
R5
C2 C3
C4
C5
C6
D1
20Ω
R1
20Ω
R2
20Ω
R3
20Ω
R4
D2 D3 D4
D5
R6
Schematic design guidelines:

USIM_VCC is the pin for supplying power only to USIM cards, and its maximum load capacity is
50 mA. USIM_VCC cannot be used to supply power to other loads.

Connect the USIM_DATA pin to USIM_VCC by using a 4.7 kΩ pull-up resistor in the external
design since the USIM_DATA pin is not pulled up internally.

USIM_CLK is the clock signal pin of the USIM card.

In applications with complex electromagnetic environments that have high requirements for ESD
protection, it is recommended to configure ESD protection components (with a junction
capacitance less than or equal to 7 pF) on each signal cable.

Connect a resistor with a resistance not greater than 20 Ω respectively to USIM_DATA,
USIM_RESET, USIM_CLK, and USIM_DET in series close to the card connector to enhance the
ESD performance.

C1-C5 are high-frequency filter capacitors on each signal cable, and the capacitance is less than
or equal to 10 pF.