UCC28180: Peripheral circuit design in UCC28180

Hi Jenny

You could look at the reference design TIDA-00443 - this is a 900W design but it will give you an idea of what a 1kW design should look like.

The bias power can be supplied by a small flyback supply - the UCC28700 is a good controller to use here.

For reverse polarity protection I'd suggest that you look at the LM74610 device. This is intended for battery applications where the voltages are lower than in a PFC output but it could be adapted for this application.
I'm not sure why you need reverse polarity protection on the output of a PFC stage - there is no mechanism to generate a negative voltage on the output and in any case if there was an output voltage reversal it would be clamped by the series combination of the PFC MOSFET and the boost diode. This path is inherent in the topology.

Regards
Colin

Dear Colin：

On the reverse polarity protection, I should be described as: Output wire plug protection, because my power supply is divided into two parts: one part is AC TO DC; the other part is DC to DC; two power supply is connected via cable Our customers have asked us to have this feature.

Looking forward to your reply
Thank you!

michael

Hi Michael

Thanks - that's a bit clearer. The simplest and most effective way to ensure that the DC/DC stage is connected correctly is to use a polarised plug - effectively a mechanical protection against someone reversing the connections. Is this something you can do ?

The LM74610 can protect the DC/DC stage from a wrong polarity connection - with modifications to allow it to operate at 400V or so.

Regards
Colin

Colin：
Your method, I communicate with the customer, but because of structural problems, the customer does not agree to modify the connector

LM74610. Is this polarity in reverse protected IC capable of being connected to an input or an output?

Hello
The LM74610 is connected to the input of the DC/DC converter - you will have to add a suitably rated MOSFET switch and make sure that the 42V cathode to anode rating of the LM74610 is not exceeded. For a 400V input that means you will need some potential divider.
Regards
Colin

Colin：
There are two more questions you need to answer.
A.UCC28180 IC output power can do 2KW? If so, can you provide a reference circuit?
B.UCC28180 how to do the input voltage protection: input over voltage protection and under voltage protection, must cut off the AC input. (May eventually need to relay, peripheral control circuit to do).
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Looking forward to your reply
Thank you!
michael

Hello Michael

The controller itself can certainly work to control a 2kW power train the problem is that the currents in the boost stage start to get large and this power level is above the level at which we would normally recommend a single phase CCM controller - in summary it will work but not optimally.

At this power level we would normally recommend a 2 phase interleaved CCM PFC based on the UCC28070A controller - I'd suggest you have a look at it.

As regards input voltage protection - input voltage UVLO would have to be done externally.

Input over voltage protection - again this must be provided externally.  Protection against transients (lightening surge tests to IEC61000-4-5 for example) is normally provided by Varistors or similar.

regards

Colin

Colin：
Thank you for your patience to help me answer the question. Your reply to my information is important to me. I'm truly grateful for your help.
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michael

Hi Michael

You are welcome.

Regards
Colin