Product Info

Smart LTE Module Series
SC66 Hardware Design
SC66_Hardware_Design 60 / 139
TXS0104
EPWR
RXD_3.3V
CTS_3.3V
VCCA
Module
GND
GND
1.8V
VCCB
3.3V
DIN1
ROUT3
ROUT 2
ROUT1
DIN4
DIN3
DIN2
DIN 5
FORCEON
3.3V
DOUT1
DOUT2
DOUT3
DOUT4
DOUT5
RIN3
RIN2
RIN1
VCC GND
OE
SN65C3238
DB-9
RTS
TXD
CTS
RXD
GND
RTS_3.3V
UART6_TXD
UART6_RTS
UART6_RXD
UART6_CTS
TXD_1.8V
RTS_1.8V
RXD_1.8V
CTS_1.8V
/FORCEOFF
/INVALID
R1OUTB
TXD_3.3V
Figure 18: RS232 Level Match Circuit (for UART5)
Debug UART, UART1, LPI_UART_2 are similar to UART6. Please refer to UART6 reference circuit
design for DEBUG UART, UART1, LPI_UART_2.
3.11. (U)SIM Interfaces
SC66 provides two (U)SIM interfaces which both meet ETSI and IMT-2000 requirements. Dual SIM Dual
Standby is supported by default. Both 1.8V and 2.95V (U)SIM cards are supported, and the (U)SIM
interfaces are powered by the dedicated low dropout regulators in SC66 module.
Table 17: Pin Definition of (U)SIM Interfaces
Pin Name Pin No. I/O Description Comment
USIM1_DET 145 DI
(U)SIM1 card insertion
detection
Active low.
Need external pull-up to 1.8V.
If unused, keep this pin open.
Disabled by default, and can be
enabled through software
configuration.
USIM1_RST 144 DO (U)SIM1 card reset signal
Cannot be multiplexed into
general-purpose GPIOs.
USIM1_CLK 143 DO (U)SIM1 card clock signal
USIM1_DATA 142 IO (U)SIM1 card data signal
Pull up to USIM1 with a 10KΩ
resistor.
NOTE