TPS7A91: Behavior at 3.3V applied voltage on output with no Vin

Jejomar Ildefonso

Part Number: TPS7A91

Hi Team,

Our customer has an irregular condition wherein an external source is connected to their circuitry which would directly apply 3.3V on the TPS7A91 output, with no Vin supplied. Will this potentially damage the TPS7A91?

Thanks in advance!

Kind Regards,

Jejomar

over 3 years ago

+1 Kyle Van Renterghem over 3 years ago

TI__Genius 13085 points

Hi Jejomar,

Unfortunately, this will violate abs max (Vout<Vin+0.3V) and it cause reverse current to flow from Vout to Vin damaging the LDO (this is true of all LDO which do not have a reverse current protection feature). To learn more about reverse current in LDOs please see the following link which explains why reverse current occurs and what can be done to prevent it.

e2e.ti.com/.../ldo-basics-preventing-reverse-current-in-ldos

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TPS7A91: Behavior at 3.3V applied voltage on output with no Vin