UC2825A: Max. Duty Cycle?

Furkan Fehmi Sefiloglu

Part Number: UC2825A
Other Parts Discussed in Thread: UC2823A

Hi Team,

Can you please check and advise with following request?

For the max duty cycle value, the expression 50% in the "ordering information" part and the expression 85% in the "electrical characteristics" part are used in the datasheet.

It is important that the max duty cycle is 50% for our practice. For this reason, can we confirm that the max duty cycle value is 50% for the two PN below?

UC2825ADW max duty: 50% ???
UC2825AQDWRQ1 max duty: 50% ???

Thanks in advance

Best Regards

Furkan Sefiloglu

over 4 years ago

0 Steven Mappus1 over 4 years ago

TI__Mastermind 32955 points

Furkan,

Yes, UC2825A is <50% asynchronous operation as shown below:

Regards,

Steve M

0 MUSTAFA CAGLAR over 4 years ago in reply to Steven Mappus1

Prodigy 20 points

Steven,

We wanted to be sure because as it seems in below picture it is stated as %85 duty in the electrıcal characteristics part.

Thank you very much for your answer.

Regards,

Mustafa C

+1 Steven Mappus1 over 4 years ago in reply to MUSTAFA CAGLAR

TI__Mastermind 32955 points

Mustafa,

The data sheet is converging a family of ICs where some are limited to <50% and others are limited to <100%, The 85% shown in the data sheet is the minimum, maximum for the UC2823A/B. This means that when rise/ fall time delays from four edges and maximum dead-times delays are considered, the worst case maximum duty cycle will be 85% (not 100%). Similarly for UC2825A/B, the minimum, maximum duty cycle will be something like ~48-49% and not 50%.

Regards,

Steve M

0 MUSTAFA CAGLAR over 4 years ago in reply to Steven Mappus1

Prodigy 20 points

Steven,

Thank you very much, it was really helpful.

Regards,

Mustafa C

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UC2825A: Max. Duty Cycle?