Smart Module Series
SC262R_Series_Hardware_Design 46 / 115
design.
VCCA
VCCB
OE
A1
A2
A3
A4
GND
B1
B2
B3
B4
LDO5_1V8
UART5_RTS
UART5_RXD
UART5_CTS
UART5_TXD
RTS_3.3V
RXD_3.3V
CTS_3.3V
TXD_3.3V
VDD_3.3V
C1
100 pF
C2
U1
100 pF
Figure 14: Reference Circuit with Voltage Level Translator Chip (for UART5)
The following figure is an example of connection between the module and PC. It is recommended to add
a level translator and an RS-232 level translator chip between the module and PC. The following figure
shows the reference design.
RTS_3.3V
RXD_3.3V
CTS_3.3V
TXD_3.3V
RTS_1.8V
RXD_1.8V
CTS_1.8V
TXD_1.8V
VCCA
Module
GND
GND
1.8 V
VCCB
3.3 V
DIN1
ROUT3
ROUT2
ROUT1
DIN4
DIN3
DIN2
DIN5
R1OUTB
FORCEON
/FORCEOFF
/INVALID
3.3 V
DOUT1
DOUT2
DOUT3
DOUT4
DOUT5
RIN3
RIN2
RIN1
VCC
GND
OE
DB-9
RTS
TXD
CTS
RXD
GND
UART5_RXD
UART5_TXD
UART5_RTS
UART5_RXD
UART5_CTS
Figure 15: RS-232 Level Match Circuit (for UART5)
UART2 and UART1 are similar to UART5. For the reference design, refer to that of UART5.
NOTE