This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

UC1823A functions

Other Parts Discussed in Thread: UC1823A, UC3823A, UC2823A, UC1823, UC3825, UC3825A, UC3825B, UC3823B, UC3823, UC1825A

Hi,

As i check from the dataheet of UC1823A, it has %100 maximum duty cycle of each output.

1) Are two PWM outputs of UC1823A in phase?

2) Does each output have %100 maximum duty with same phase?

3) Can i drive the mosfets of 2xseparete buck converter with one UC1823A (by using high side gate driver IC)?

4) What is the difference between UC3823A and UC1823A?

5) What does highlighted sentence mean at the attached figure?

Thank you.

  • Hi,

    Waiting for responses,thank you.

  • gG,
    1) Are two PWM outputs of UC1823A in phase?

    Response: As highlighted in the datasheet pg.2 UC2823A outputs operate in phase with duty cycle from zero to less than 100%.

    2) Does each output have %100 maximum duty with same phase?

    Response: Each output has duty cycle from zero to less than 100% with both outputs in phase.

    3) Can i drive the mosfets of 2xseparete buck converter with one UC1823A (by using high side gate driver IC)?

    Response: Need more clarification with your question, can you email your schematic , so I can see how the feedback is connected in your circuit, with two buck converters.


    4) What is the difference between UC3823A and UC1823A?

    Response: I am assuming you want difference between UC1823 vs UC1823A
    The UC3825A and UC3825B have dual alternating outputs and the same pin configuration of the UC3825. The UC3823A
    and UC3823B outputs operate in phase with duty cycles from zero to less than 100%. The pin configuration of the UC3823A
    and UC3823B is the same as the UC3823 except pin 11 is now an output pin instead of the reference pin to the current
    limit comparator. “A” version parts have UVLO thresholds identical to the original UC3823 and UC3825. The “B” versions
    have UVLO thresholds of 16 V and 10 V, intended for ease of use in off-line applications.

    5) What does highlighted sentence mean at the attached figure?

    Response: This is implying that the two outputs are in phase for UC1823A whereas for UC1825A the two outputs are out of phase
  • gG

    Also note UC1823A is a dual output whereas UC1823 is a single output.

    As indicated in the datasheet :
    The pin configuration of the UC3823A and UC3823B is the same as the UC3823 except pin 11 is now an output pin instead of the reference pin to the current limit comparator.