TCA9802: Using as a bus repeater with multiple devices

Damien Frost1

Prodigy 30 points

Part Number: TCA9802

Hi Everyone,

I would like to know if I can use the TCA980x in the configuration shown below as a type of bus repeater. It features:

A single power supply for all devices
Slave devices along the length of the bus in between the TCA980xs

Thanks,

Damien

over 5 years ago

0 Clemens Ladisch over 5 years ago

Guru 303260 points

This will work. But every repeater adds its propagation delay, so it might be necessary to reduce the frequency. (Check the timing at the last slave.)

Why so many repeaters? Are the bus segments actually larger than shown above? Would it be possible to use a star topology?

0 BOBBY over 5 years ago

TI__Guru 64980 points

One thing to note, your bus on the master side needs pull up resistors but all other nodes with B side of TCA980x do not.

-Bobby

0 Damien Frost1 over 5 years ago in reply to Clemens Ladisch

Prodigy 30 points

Excellent thanks for the quick feedback. Noted about the frequency.

The bus segments will be long and all in a line, hence the topology. A star topology will not work for this application.

0 Damien Frost1 over 5 years ago in reply to BOBBY

Prodigy 30 points

Thanks for the reminder, I just forgot to add them to my drawing.

Interface

Interface forum

TCA9802: Using as a bus repeater with multiple devices