• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 451 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

UCC28730: 3-phase AC/DC with full-wave bridge rectifier - HV pin at risk?

tc
Prodigy 140 points
Part Number: UCC28730
Other Parts Discussed in Thread: TIDA-01560, , UCC28701, UCC28722

Hi,

I'm designing a 3-phase PSU and the TIDA-01560 ref design meets my requirements.  I'd like to alter the AC input adding a 3phase full-wave bridge rectifier to this ref design, and then replace the Mosfet with a higher voltage model, and have the following questions:-

1. Do you have an EMC filter design suitable for 3phase that you can recommend.

2. For 230Vac phase-to-neutral voltage with full-wave rectification, the DC voltage will be ~566V.  If the 3-ph phase-to-neutral voltages exceed 285Vac then the DC voltage will exceed the 700V limit for the HV pin.  Can I protect the HV pin for this situation?

3. Is there anything else I need to consider or alter for this wide input range design?

Thanks

Tony

  • 0
    TI__Guru* 80016 points

    Hello,

    The HV pin is used for trickle charge of the VDD capacitor and the current is low.  You could use a TVS diode in series with this pin to ensure that maximum voltage of 700V is not exceeded.

    You could use the UCC28701 PSR flyback controller instead  of the UCC28730.  This uses a trickle charge resistor instead of an internal JFET like the UCC28730.

    The following is a link that will bring you to an application note using the UCC28722 PSR for eMeter applications.  These are wide input range designs and this information is applicable to your design and you may find it helpful.

    The following link will bring to a training Video that will aid with your EMI filter design.

    Regards,