UCC28C4x : Overcurrent limitation

alpha

Expert 2530 points

Our customer thinks that UCC28C4x can limit over current by cycle-by-cycle at CS pin.

How much is threshold value at CS pin?
Is maximum input voltage 1V?

Best regards.

over 9 years ago

0 Peter Meaney over 9 years ago

TI__Mastermind 31580 points

Yes the UCC28C4x devices have a cycle by cycle current limit set a 1V typical. The CS pin range is is 0.9V to 1.1V.

Regards

Peter

0 alpha over 9 years ago in reply to Peter Meaney

Expert 2530 points

Hi Peter

Thank you for your reply.
Could you tell how much is threshold to set a cycle by cycle current limit?

Best regards.

0 Peter Meaney over 9 years ago in reply to alpha

TI__Mastermind 31580 points

Hi

I am not sure I fully understand your question.

The primary current sense resistor will have a voltage across it porportional to the primary current flowing in the transformer.The input current is scaled by the transformer turns ratio to the secondary current. By varying the resistance of the primary side current sense resistor, the value of the secondary current at which the IC hits the cycle by cycle peak current limit can be adjusted.

Regards

Peter

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UCC28C4x : Overcurrent limitation