REF200: Functional Failure

Dylan You

Part Number: REF200

Dear Teams,

My customer is using REF200 plus INA326 for PT1000 Sensor solution. Following picture is the schematic diagram.

Recently, they found that there is a phenomenon of functional failure. It is suspected that the output of REF200 may be short-circuited to GND.

Support Need:
1. Can pin 1 of REF200 be short-circuited to GND for a long time? There is a short circuit in the actual application,
2. How to add protective measures in the circuit to avoid damage to REF200?

Thanks!
Dylan

over 3 years ago

0 Ajay Padgaonkar over 3 years ago

TI__Intellectual 1695 points

Dylan, I have asked Marcoo, our expert on this product family, to review and reply. Sorry to keep you waiting. ..ajay

+1 Marcoo Z over 3 years ago

TI__Mastermind 19550 points

Hi Dylon,

The REF200 needs some kind of resistance or load to be able to regulate properly. when the device is shorted to GND the REF200 cannot operate properly.

I would add a small resistance between pin one and the junction of J1 and R4 on both strings. The resistance should not affect the voltage measurement since it is in series with the DUT. This way if 3,2,1 are shorted to gNd the device can regulate the series resistance.

0 Dylan You over 3 years ago in reply to Marcoo Z

TI__Intellectual 2630 points

Hi Marcoo,

Thanks a lot for your strong support. This solve the problem for my customer. Thanks!

Dylan

Power management

Power management forum

REF200: Functional Failure