TPS23756: TPS23756 Transformer Polarity/Phase Required?

eljeffo

Intellectual 560 points

Part Number: TPS23756

Hi,

It turns out that my PCB layout may benefit from hooking up the primary transformer pins "backwards".

It seems the bias Vc already has a diode and won't really care.

I'm curious, does the primary/secondary coil phase/polarity need to match for proper operation?

Jeff

over 4 years ago

0 Michael Pahl over 4 years ago

TI__Mastermind 21320 points

Jeff,

Yes it absolutely needs to match. I have had transformers made backwards and they do not work. However, you could work with a transformer vendor and ask them to flip the polarity for you if your layout is already done.

If this post answers your question, please indicate so by marking this thread as resolved. Thank you.

Regards,

Michael P.

Applications Engineer

Texas Instruments

0 eljeffo over 4 years ago in reply to Michael Pahl

Intellectual 560 points

Thanks Michael. Appreciate the reply. At worst, perhaps I'll just hook up both the primary and secondary backwards to keep everything "the same"

0 Michael Pahl over 4 years ago in reply to eljeffo

TI__Mastermind 21320 points

Jeff,

Also be sure to include the bias winding for the IC if you are wiring things backwards. I would not recommend it.

If this post answers your question, please indicate so by marking this thread as resolved. Thank you.

Regards,

Michael P.

Applications Engineer

Texas Instruments

0 eljeffo over 4 years ago in reply to Michael Pahl

Intellectual 560 points

Thanks for your insight Michael!

If you have any whitepapers I should read to understand the role of GATE2 in the TPS23756 circuit more, please let me know. I'm far far far from a power engineer and would love to learn more.

0 Michael Pahl over 4 years ago in reply to eljeffo

TI__Mastermind 21320 points

Jeff,

It is used in topologies that use multiple FETs or pulsed transformers, such as active clamp forward or driven flybacks.

An example is PMP6584

If this post answers your question, please indicate so by marking this thread as resolved. Thank you.

Regards,

Michael P.

Applications Engineer

Texas Instruments

0 eljeffo over 4 years ago in reply to Michael Pahl

Intellectual 560 points

Thanks Michael, I'll go read what I can find. Have a great day!

0 eljeffo over 4 years ago in reply to eljeffo

Intellectual 560 points

Michael,

Thanks to your help, I have a 5v output and understand the basic operation of the circuit.

Jeff

Power management

Power management forum

TPS23756: TPS23756 Transformer Polarity/Phase Required?