MAX660: Output failure mode

Danilo A.

Part Number: MAX660

Hi Team,

Can you please help with this inquiry of our customer?

My associate is claiming this part has a fault condition whereby the inverted output can go positive during start up mode

I.E. as a +3 to -3V converter that during start up the output goes positive and tracks the +3V input. He suggests we add a protection diode to Vout to block this .. I am having difficulty understand how this could be possible, any thoughts?

"add Schottky (ZLLS410TA) diode from -3V to GND to prevent -3V bus form going positive in startup and fault conditions."

Regards,

Danilo

over 1 year ago

0 Niklas Schwarz over 1 year ago

TI__Mastermind 20330 points

Hi Danilo,

Thanks for using the e2e forum.
I am sorry you did not receive a response until now.

I will look into this behavior and give you an update by tomorrow.
In the meantime, can you share a schematic of the customers application?
This should make it easier to pin down the source of the error.

Thank you and best regards,
Niklas

0 Niklas Schwarz over 1 year ago in reply to Niklas Schwarz

TI__Mastermind 20330 points

Hi Danilo,

One additional request,
Could you provide a measurement of the failure from the customer?

Thanks you very much.
Best regards,
Niklas

0 Danilo A. over 1 year ago in reply to Niklas Schwarz

TI__Mastermind 25675 points

Hi Niklas,

According to our customer,

There is no failure we are using the part exactly as called out in the data sheet I posed a question specifically

We were told by co worker that unless we added a schottky diode between output pin 5 and ground the max660 locks up during start up.

Is this True? Yes or no and why

Regards,

Danilo

0 Brigitte over 1 year ago in reply to Danilo A.

TI__Guru 59605 points

Hello Danilo,

Ah, so this is not an issue, but you fear that it could happen, now I understand. I did not see this behavior up to now, so I would expect that this is not an issue, but if you want to be on the safe side, you could place a diode on the output and not populate it.

Best regards,
Brigitte

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MAX660: Output failure mode