Smart Module Series
SC262R_Series_Hardware_Design 49 / 115
⚫
In order to ensure good ESD protection, it is recommended to add a TVS array with parasitic
capacitance not exceeding 50 pF
. Add 22 Ω resistors in series between the module and (U)SIM card
to suppress EMI spurious transmission and enhance ESD protection. Please note that the (U)SIM
peripheral circuit should be close to the (U)SIM card connector.
⚫
Add 22 pF capacitors in parallel on USIM_DATA, USIM_CLK and USIM_RST signal lines to filter RF
interference, and place them as close to the
(U)SIM
card connector as possible.
⚫
Place the reserved pull-up resistors R6 and R5 in
: Reference Circuit for (U)SIM Interface
with an 8-pin (U)SIM Card Connector and
: Reference Circuit for (U)SIM Interface with a
6-pin (U)SIM Card Connector close to the module.
3.12. SD Card Interface
SD Card interface of SC262R series module supports SD 3.0 protocol. The pin definition of SD card
interface is shown below.
Table 13: Pin Definition of SD Card Interface
A reference circuit for the SD card interface is shown below.
Pin Name
Pin No.
I/O
Description
Comment
SD_CLK
39
DO
SD card clock
50
Ω characteristic
impedance.
SD_CMD
40
DIO
SD card command
SD_DATA0
41
DIO
SDIO data bit 0
SD_DATA1
42
DIO
SDIO data bit 1
SD_DATA2
43
DIO
SDIO data bit 2
SD_DATA3
44
DIO
SDIO data bit 3
SD_DET
45
DI
SD card hot-plug detect
Active low.
SD_LDO11
38
PO
SD card power supply
Vnom = 2.95 V
I
O
max = 800 mA
SD_LDO12
32
PO
1.8/2.95 V output power supply for SD
card pull-up circuits.
Vnom = 1.8/2.95 V
I
O
max = 50 mA
