UCC2894: About sink current for VREF pin

Satoshi

Guru 19645 points

Part Number: UCC2894

One customer is planning to addition the external circuit for sink current flow to VREF pin.

Please let me know about two points below,

①Is there spec for VREF maximum sink current?

②Is UCC2894 specification(Vout accuracy, ripple, etc.) depend on VREF sink current?

Best regards,

Satoshi

over 5 years ago

0 Sonal Singh over 5 years ago

TI__Expert 6080 points

Hello Satoshi,

The VREF pin can supply a maximum of 5mA to the external circuits. If you stay within this 5mA current rating then there should be no impact on the controller performance, but the power stage should remain fairly unaffected.

Regards,

Sonal

0 Satoshi over 5 years ago in reply to Sonal Singh

Guru 19645 points

Sonal san

Thank you for reply,

Please let me confirm about above Q&A;

Can UCC2894 use on "external sink circuit" to VREF input?

I worry about possibility to increase VREF voltage by external sink.

I want to clear these careful points. (The hope is; VREF is not increase, and the other no problem)

Best regards,

Satoshi

0 Satoshi over 5 years ago in reply to Satoshi

Guru 19645 points

Any update on this?

0 Satoshi over 5 years ago in reply to Satoshi

Guru 19645 points

Please let me know your review status.

0 Sonal Singh over 5 years ago in reply to Satoshi

TI__Expert 6080 points

Hello Satoshi,

You may use a simple 5V Zener to clamp to your external circuit if this is a point of concern, but the Iref is internally limited to 5mA.

Regards,

Sonal

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UCC2894: About sink current for VREF pin