TPS543C20: Remote Sense Placement and routing

Ajmal Rashid

Part Number: TPS543C20

Tool/software:

Hi Team,

I'm using TPS543C20RVFT part ( master and slave configuration) to generate 0.72V @60A.

From the 'WEBENCH® Power Designer' tool, i have generated the schematics for the same (Please find the attachment 'Simulation').

Here i'm going to use the remote sensing feature to sense the voltage at the load side. But i'm confused about the placement for remote sensing components.

Please find the attachment 'RemoteSensingPlacementPlan'. As mentioned on this snapshot, below are the planning for placement and routing, please check this is okay or not. And let me know, anything else to be taken care

1- Place all the remote sensing and feedback resistor components near to IC

2- Route a trace from Rfbt resistor which is placed near to regulator to Load pin ( Please refer the green colour trace) with 50E impdance

4 months ago

0 Britton Jones 4 months ago

TI__Expert 7316 points

Hello,

What you described in steps 1 and 2 is correct, but there is a third point to remember.

3. Route RSN to the GND near the load along a similar path as the green trace. It is essential to route the RSP and RSN pins as a pair of diff-traces. Try to match the length of the traces.

Best regards,

Britton

0 Ajmal Rashid 4 months ago in reply to Britton Jones

Prodigy 90 points

Thanks for your input

Please find the above snapshot for the example layout and routing.

Here, if we place one 0E near to 'Rfbt', we can route 100E differential signal from 'Rfbt' to Load input pins.

Also, we can do the differential 100E routing from regulator RSP/RSN pins to 'Rrsp'/ 'Rrsn' resistor.

But the problem is, in the RSN line, only a 10E series resisor is coming. But RSP line having the 287E and 10KE for feedback. So how to do the differential 100E routing ?

If you have some exmaple layout for this, please share

0 Calan Elaya 4 months ago in reply to Ajmal Rashid

TI__Expert 8245 points

Hello,

Please allow Britton some time to get back to you on this, as there is Thanksgiving U.S. Holiday.

Thanks,
Calan

0 Britton Jones 4 months ago in reply to Ajmal Rashid

TI__Expert 7316 points

Hello,

The only layout example I have is for a local evaluation module so the trace is likely much shorter than your condition. https://www.ti.com/lit/ug/sluubw8a/sluubw8a.pdf?ts=1732235647787&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FTPS543C20EVM-054

But I would route in the following way:

Keep the 10E and 0E placeholder in the RSN path. In the top path place the feedback resistors Rfbt and Rfbb close to the IC. Then, the Rrsp 10E resistor goes between the load and Rfbt. Rrsp also operates as a test point for stability in this position. Then just route the pair next to each other back to the load with a similar length trace.

Best regards,

Britton

0 Ajmal Rashid 4 months ago in reply to Britton Jones

Prodigy 90 points

Hi Britton,

Thanks for your suggestion.

For the final confirmation, please check the below snapshot for the final routing plan

+1 Britton Jones 4 months ago in reply to Ajmal Rashid

TI__Expert 7316 points

That looks good.

Best regards,

Power management

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TPS543C20: Remote Sense Placement and routing