UC1825A-SP: 50% maximum duty cycle?

Hisui Yan

Part Number: UC1825A-SP
Other Parts Discussed in Thread: UC1825-SP, UC1825B-SP

The datasheet of UC1825A-SP said that “The UC1825A-SP outputs are alternately controlled”, so that duty cycle varies “from 0 to less than 50%”. However, in Fig. 15 of the datasheet, the maximum duty cycle can reach 100%. Besides, the datasheet of UC1825-SP does not have the description about the 50% limit of duty cycle. So, could you clarify: (1) what is the maximum output duty cycle of UC1825A-SP? (2) what is the maximum output duty cycle of UC1825-SP?

over 4 years ago

0 Daniel Hartung over 4 years ago

TI__Mastermind 26825 points

Hey Hisui,

Both the UC1825-SP and the UC1825B-SP have a maximum duty cycle per phase (OUTA/OUTB) of 50%.

Where it talks about the maximum duty cycle going to 100%, it is adding both of the phases together.

Thanks,

Daniel

0 Hisui Yan over 4 years ago in reply to Daniel Hartung

Prodigy 180 points

Hello Daniel,

Thanks for your clarification about maximum duty cycle of UC1825-SP and the UC1825B-SP. But, how about UC1825A-SP?

Besides, "the adding both of the phases together" means to add duty cycle of OUTA and OUTB, right?

0 Daniel Hartung over 4 years ago in reply to Hisui Yan

TI__Mastermind 26825 points

Hey Hisui,

This is true for the UC1825A-SP as well.

Adding both the phases together does mean add the duty cycle of OUTA and OUTB.

Thanks,

Daniel

Power management

Power management forum

UC1825A-SP: 50% maximum duty cycle?