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TIDA-00708: Low power isolated dc/dc (400/12V) converter

Part Number: TIDA-00708

Hi all,

I am looking for a isolated DC/DC converter with the following features:

Vin: 270 to 450V DC

Vout: 9-15V

Pout: 0 - 10W

Efficiency > 80% at (20-100% loading)

Single Output: 12 V/0.015-1 A (Isolated)

Safety Features : Short Circuit, Overload and Undervoltage protection

Does TI have an off-the shelf product that meet this specifications?...TIDA-00708 is a good reference design but I want to cover a slightly larger power range.

What would be the expected volume and cost of such a dc/dc converter?

Thank you in advance.

Evangelos

  • Hi Evangelos,

    Thank you for reaching out. Have you seen our TI Power Reference Design Library? If you go to www.ti.com/tidesigns and click "Search power designs by parameters," you can search our library of ~2,000 built and tested power supplies.

    After inputting your parameters, I was able to find PMP8678, http://www.ti.com/tool/PMP8678?keyMatch=null&tisearch=tidesigns-power, which seems to match what you are looking for. It is a flyback solution that leverages a low-cost IC and BJT switch. This implementation is non-isolated. However, isolation can be achieved through another winding on the transformer or an optocoupler.

    I think the overall cost will be dominated by the transformer and high voltage caps. I would guess that the overall solution could come in around ~$10. This is just a ballpark estimate.

    Thanks,
    Ryan

  • Hi Ryan,

    Thank you for your reply. Isolation is an important requirement so I would have to go for another winding. However, PMP8678 is very close to my specifications.

    I saw that when the maximum current is reached the converter behaves as a current source. Would it be possible to increase the value of the output capacitance and have a transient load response ? For example, to have a design that can provide a current of 2-3Amps @ 12V for 5ms ?

    Moreover, can I configure the design of the flyback solution of PMP8678 with my own transformer and order several devices from TI ?
    How is the purchasing process?...Excuse me if these questions are irrelevant to you but I am new in the forum.

    Thank you in advance.

    Best Regards,
    Evangelos
  • Hi Evangelos,

    Sure, you can increase the output capacitance to support the hold-up during transient events. The power supply will act as a current-source as you mention during startup and transient events. Keep an eye on the thermals of the FET and transformer during these events as you will be in current limiting.

    We can not provide PMP8678. However, the Gerber files are available online. You can order UCC28720 and TPS560200 samples from the TI Estore, https://store.ti.com/default.aspx

    Ryan