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SIM7600NA_user manual _V1.00 30
2020-1-7
Figure 13: UART full modem
Figure 14: UART null modem
The MODULE 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 TXB0108RGYR
provided by Texas Instruments is recommended. The following figure shows the voltage matching
reference design.
Figure 15: Reference circuit of level shift
User can use another level shifter circuits as follow