TPS23754: Schematic review

Denny Huang

Expert 7170 points

Part Number: TPS23754
Other Parts Discussed in Thread: TL431,

Dear team

There is a good news that we design in TPS23754 in customer's new project.

Could you help to review the schematic?

Many thanks

Denny

over 3 years ago

0 Michael Pahl over 3 years ago

TI__Mastermind 21320 points

Hey Denny,

I can finish this by EOB this week.

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 Michael Pahl over 3 years ago in reply to Michael Pahl

TI__Mastermind 21320 points

Hey Denny,

Can you send me a PDF of the schematic?

The part numbers are too blurry to read. Thank you.

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 Michael Pahl over 3 years ago in reply to Michael Pahl

TI__Mastermind 21320 points

VHey Denny,

Thank you for sending the schematic. I assume they base it on PMP6672.

For further guidance, please have the customer review PoE PD Schematic Review Guide

https://www.ti.com/lit/an/slvaf59/slvaf59.pdf?ts=1623770103653&ref_url=https%253A%252F%252Fwww.google.com%252F

Here is some feedback:

- They do not need dividers for both PPD and APD. I assume their adpater is 48V or higher, so we can remove PPD divider. So DNP R7302. They could remove R7302 and R7304 and connect PPD to VSS.

- D7307 has a reverse recovery time of 50ns, whereas the one used in PMP6672 has 25ns. The 50ns delay may be too long to catch the rising edge of the Vds. Therefore a faster diode should be chosen.

- the CS pin has a 330pF cap to help filter the signal. I would advise at least a place holder for a capacitor here. I have found this capacitor can make the difference in stability of the design.

- U7303 should be the TLV431 not the TL431 https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/552603/what-difference-between-tlv-lmv-tl431

- Q7302 should have a higher Vds rating. We use 40V, they use 30v.

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 Denny Huang over 3 years ago in reply to Michael Pahl

TI__Expert 7170 points

Hi Michael

Thanks you recommend.

What is the difference between TPS23754EVM-420 EVM and PMP6672.
The customer have seen that some materials are different, but the general structure is the same.
Is it the difference between the new version and the old version?

Many thanks

Denny

0 Michael Pahl over 3 years ago in reply to Denny Huang

TI__Mastermind 21320 points

The PMP6672 is the optimized version of the TPS23754EVM-420. Sometimes we revisit popular designs and optimize them for efficiency or cost after we do the work of releasing the new IC.

I would recommend following the PMP6672.

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

Regards,

Michael P.

Applications Engineer

Texas Instruments

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TPS23754: Schematic review