TPS22918: Sequence requirment

tateo yamashiro

Part Number: TPS22918
Other Parts Discussed in Thread: TPS22975

Hi,

We got a question from customer about TPS22918.
Could you help us?

[Question]
Is there any sequence requirement between VIN and ON?
In their application, when Vin voltage is not supplied, EN voltage is supplied. Is there any concerns about this usage?

Best Regards,
tateo

over 7 years ago

0 Aleksandras_Kaknevicius over 7 years ago

TI__Genius 15710 points

Hi Tateo,

It will not damage the device to have ON pulled high and VIN not supplied, but there may not be a controlled rise time on VOUT once VIN is applied because the part has not had a chance to power up. In other words, VOUT may just follow VIN since the device is already enabled.

Thanks,

Alek Kaknevicius

0 tateo yamashiro over 7 years ago in reply to Aleksandras_Kaknevicius

Guru 10890 points

Thank you for your reply. Let me confirm about TPS22975 too.

Is there any sequence requirement between VIN, VBIAS and ON? In their Application, there is possibility that when VIN and VBIAS are not supplied, ON is pulled high.

Best Regards,

tateo

0 Aleksandras_Kaknevicius over 7 years ago in reply to tateo yamashiro

TI__Genius 15710 points

Hi Tateo,

The optimal power sequencing is applying VIN and VBIAS before the ON pin is pulled high. If the ON pin is pulled high before then, the device will not be damaged but the rise time may not be controlled (VOUT may follow VIN).

Thanks,

Alek Kaknevicius

Power management

Power management forum

TPS22918: Sequence requirment