THVD1520: Sequence

Brian Wang0928

Part Number: THVD1520

When designing a RS485 in the system, is there power sequence requirement?

What if the MCU's signal sends to Drive pin of RS485 device before its VCC is powered? We'd like to know if there is a concern on the power sequence.

Regards

Brian

over 3 years ago

0 Clemens Ladisch over 3 years ago

Guru 320600 points

This is no problem; see [FAQ] Can the input voltage (Vi) to my logic device be higher than the supply voltage (Vcc)?

+1 Parker Dodson over 3 years ago

TI__Guru 53912 points

Hi Brian,

Clemens is correct - there shouldn't be an issue for this device as the abs max table doesn't indicate positive clamping diodes (input voltages maximums are static instead of referred to as VCC + X Volts) and there isn't an input clamp current rating as well - the reasoning why can be found in the FAQ that Clemens linked.

Please let me know if you have any other questions and I will see what I can do!

Best,

Parker Dodson

Interface

Interface forum

THVD1520: Sequence