Users Manual Part 2

SIM8260A_Hardware Design_V1.05
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3.11 UART Interface
SIM8260A default supports 3 UART ports for communication, which data rate up to 4Mbps. All the UART
level of SIM8260A is 1.8V. If it communicates with the 3.3V serial port level, a level conversion chip needs
to be added in the middle. It is recommended to use TXS0104EPWR level shift of TI, the reference circuit
is as follows.
Figure 33: UART level conversion circuit
The following level shifting circuits can also be used:
Figure 34: UART TX level conversion circuit