Do you have any RS-485 compliant termination selector which is controlled by one of the Digital output of the micro controller
Application would be RS-485 transceiver where the termination resistor requires a switch and it shall be software selectable.
Shashank,
There are many switches that can be controlled with software. TI switches are typically controlled with GPIOs from a processor or microcontroller and can be found using the TI.com switch selection tool.
Just like finding a switch for any signal standard you need to know the signal standard number of data lanes (channel count), voltage range, and datarate/bandwidth. All of these devices will support any signal like RS485 as long as the signal voltage and bandwidth are within the recommended operating conditions.
RS485
Channel count: has 2 datalanes TX and RX (2-channel)
Voltage range: RS485 signal can range from -7V to 12 V (we will assume 0-5V signals are used for this device recommendation example)
Bandwidth: RS485 can support up to 10Mbps ( We will recommended a device with >15MHz to give some margin to support this datarate)
The ti.com switch search tool can be filtered for the above parameters and shows there are TMUX6121 device that is a close match for supporting the full range of voltage -7V to 12V or but the on-state resistance is too high for you needs. Next the SN74LVC2G66-Q1 or TS5A21366 devices have lower on-state resistance but only will only support 0-5V signals. The options will depend on how you are operating your system.
What is the voltage range of your RS485 application? Do you have a diagram of what you would like to achieve?
Thank you,
Adam
