UCC28180: Request the full spec of inductor L1 to L4 used in TIDA-00779 schematic

Ng Ka Lung

Part Number: UCC28180
Other Parts Discussed in Thread: TIDA-00779

Dear Expert,

We find that TI UCC28180D fit our requirement for PFC application. So, we are planned to build the engineer sample to evaluate this IC.

We want to follow TIDA-00779 schematic as a blueprint to build our sample.

So, we want to know the details spec for L1, L2, L3 and L4 used in the schematic.

Would we buy these inductor from the on line sale such as digikey or mouser etc?

So, we can speed up our evaluation process.

If not , would you tell us how to build these 4 inductor?

So, we just required to buy the bobbin and magnetic core from the market then build these inductors by local inductor supplier.

Thanks

Barry Ng

Senior engineer.

over 5 years ago

0 Peter Meaney over 5 years ago

TI__Mastermind 31580 points

Hi Barry,

Please see drawings attached.

common+choke+LT38-4P-014+2.5mH-30A+YUNLU.pdf

PFC+choke+029E1-001+30A+-170uH+YUNLU.pdf

Regards

Peter

0 Ng Ka Lung over 5 years ago in reply to Peter Meaney

Prodigy 90 points

Hi Peter,

Thanks for your quick support. Spec for L2, L3 and L1 are well received. Thanks a lot.

I also find L4 : Differential inductor, 10uH, TH in TIDA-00779 schematic.

Would you also give us the details spec of L4?

So, we can purchase L4 from the market.

Many Thanks

Barry Ng

Senior engineer.

0 Peter Meaney over 5 years ago in reply to Ng Ka Lung

TI__Mastermind 31580 points

Hi Barry,

I have requested the L4 drawing.

It will be Monday before I can post it.

Regards

Peter

0 Ng Ka Lung over 5 years ago in reply to Peter Meaney

Prodigy 90 points

Hi Peter,

Thanks for your great support.

We are planned to release the PCB gerber no later than 21 Aug 2020.

Would you tell us the mechanical dimension and PCB layout footprint of L4?

So, we can release the PCB layout on the planned date.

What is the function of L4 -10uH and C3 - 1uF?

I think that these two parts are installed to pass EMI/EMC test.

Which EMI/EMC test will be failed if we don't install L4 (Use jumper to short L4) and C3 (remove this part)?

We would be highly appreciated if we can know the details of the EMI/EMC failure ( which frequency? how many dB are exceeded the limit etc.)

Many thanks for your professional support.

Regards

Barry Ng

0 Peter Meaney over 5 years ago in reply to Ng Ka Lung

TI__Mastermind 31580 points

Hi Barry,

L4 is an optional part of the design and was not designed so there are no drawings for it. I suggest that you use an off the shelf part and see if it needed in the end design.

Regards

Peter

0 Ng Ka Lung over 5 years ago in reply to Peter Meaney

Prodigy 90 points

Hi Peter,

Thanks for your quick support.

What is the function of L4?

What benefit or advantage (e.g. reduce conductive emission x dB etc.) we can get if L4 is added in the circuit ?

I want to know that under what condition L4 is required to add in the circuit.

Regards

Barry Ng

0 Peter Meaney over 5 years ago in reply to Ng Ka Lung

TI__Mastermind 31580 points

Hi Barry,

The L4 is a common mode choke and will help reduce EMI due to common mode currents in the AC input.

It is impossible for me to tell you what level of reduction in EMI fitting L4 will bring to the design, my advice is to layout a position for L4 and then test the design and see if it is required or not.

Common mode current level is dependent on may factors including parasitic capacitances across the isolation barrier and are difficult to predict or calculate.

Regards

Peter

0 Ng Ka Lung over 5 years ago in reply to Peter Meaney

Prodigy 90 points

Hi Peter,

Thanks for your professional advise.

I agree that performance of EMI/EMC depends on many factors such as PCB layout etc.

We will reserve the PCB space for L4 first.

Many thanks

Regards

Barry Ng

Power management

Power management forum

UCC28180: Request the full spec of inductor L1 to L4 used in TIDA-00779 schematic