Sunsea AIoT SIMCom SIM7075G User Manual page 28

Table 12: UART electronic characteristic
Symbol Description
VIH UART input high level voltage
VIL UART input low level voltage
VOH UART output high level voltage
VOL UART output low level voltage
The SIM7075G UART is 1.8V voltage interface. If user's UART application circuit is 3.3V voltage interface,
the level shifter circuits should be used for voltage matching. The following figure shows the voltage
matching reference design.
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Figure 12: UART null modem
Figure 13: Reference circuit with level shifter IC
SIM7075G User Manual V1.00
Min. Typ. Max. Unit
1.17 1.8 2.1
-0.3 0 0.63
1.35 1.8 1.8
0 0 0.45
V
V
V
V
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