User's Manual

Chapter 5 – Test Board
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 36
SIM Schematic (5V)
SIM Schematic
GND
VIN = 5V
GND
LTC1555 SIM 3V/5V Level shifter.
GND
VCC = 2.8V
GND
R12 100K
R22 0
U6
LTC1555
8
125
6
7
11
10
9
161
13
2 15
14
4
3
M0
VINDV CC
SS
M1
C1+
C1-
GND
CLKCIN
VCC
RIN RST
I/O
DDRV
DA TA
Place C30
near pin
13 of U6.
GND
C17 2.2uF
SIMCLK
R21 0
C_GPO0
C43 2.2uFR13 100K
VCC
VIN
GND GND
C28 .1uF
R20, R21, R22 and R23
are used to shunt
LTC1555.
SIM interface from
Modem Module.
+
C30 33uF
R20 0
SIMV CC R23 0
SIMPRES1
GND
4.7K
10K
47K47K
U4
UMC5NT1
1
4
5
3
2
SIMDATA
J2
SIM_6 P
1
2
3
4
5
6
7
8
VCC
RST
CLK
CC4
GND
VPP
I/0
CC8
R15 1K
GND
SIMRST
R14 100K