UCC256304: UCC256404: HV PIN query

cyan zhou

Expert 1500 points

Part Number: UCC256304
Other Parts Discussed in Thread: UCC256404, UCC256302

Hi Sir,

I'm interested in a new device, the part number is UCC256404. YES, UCC256404, a new device. but, have a query.

our product is general inverter, system need a auxiliary power, we plan to use LLC controller UCC256404;

we don't need PFC stage, then the input of the device is 400Vdc from inverter power train Vbus,

The question is clear: Can HV PIN of UCC256404 connect to Vbus 400Vdc directly? Will this case affect the start-up of the LLC stage power？

Thanks and wait for your reply.

Regards.

Does it affect the power start

over 5 years ago

0 Eric Faraci over 5 years ago

TI__Expert 8210 points

Cyan

While UCC256404 will work if the HV pin is connected to a DC bus, the x-capacitor discharge function will continuously fail to detect a zero crossing and periodically attempt to discharge what the controller thinks is the X capacitance. This will make the controller package heat up quite a bit.

For DC input we recommend that UCC256302 is used since it does not have this issue. There is no -2 variant of UCC25640x available at this time.

Best Regards,

Eric

0 user5830659 over 5 years ago in reply to Eric Faraci

Prodigy 20 points

When UCC25640x -2 variant will be available?

0 Eric Faraci over 5 years ago in reply to user5830659

TI__Expert 8210 points

Cyan

I'm sorry, but it's against TI policy to disclose any details (such as release dates) of unannounced products.

Best Regards,

Eric

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UCC256304: UCC256404: HV PIN query