MAX3221: Are Rout are HighZ when chip is in Auto-power-down state?

B Gerber

Part Number: MAX3221

Tool/software:

Hi there.

I would like to use the MAX3221CPWR chip on my circuit.

I have a UART input OR an RS232 input connected to the PCB (not at the same time) which communicate with other hardware via an RS485 chip.

The Rout output would be interference with the UART input, if the RoutDriver would not be disable on Auto-power-down state.

I cant find any information about that in the datasheet, but i have to know it exactly.

Otherwise i have to decouple the two signal paths additionaly.

Thank you in advance!

+1 Clemens Ladisch 30 days ago

Guru 306330 points

Table 8-2 shows that (only) when the receiver is disabled by pulling /EN high, then the ROUT pin is in the high-impedance state.

To disable ROUT in the automatic power-down state, connect /INVALID to /EN with an inverter.

0 B Gerber 29 days ago in reply to Clemens Ladisch

Oh, thats a great move!
You're right - Thank you very much. That should be solve my problem :)

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