Hi,
I have two devices communicating via UART. Device 1 sends data to Device 2 through the same TX pin used by the MCU. I want to implement a switch to control the flow of data between Device 1 and Device 2. When the MCU needs to communicate with Device 2, the switch will be turned off, cutting off the data stream from Device 1. After the MCU finishes communication, the switch will be turned back on to resume the data flow from Device 1 to Device 2. What is the most reliable design to use for this switching mechanism.

Thank you,

 

" What is the most reliable design to use for this switching mechanism. "

Probably some sort of Tri-State bi-directional line buffer type of component.

 

What are the UART signal voltage levels you need to switch?

 

A reliable design would somehow inform device 1 that it should stop transmitting instead of just throwing away the data.

 

What are the UART signal voltage levels you need to switch?

The UART TX line is 3.3V, so the switch should be able to handle a 3.3V logic level for both the high and low signals

 

Analog switch TPW3157A-CR