TPSM82903: Transmiting power over 30 meter (23AWG cable)

Abhineet Ranjan

Part Number: TPSM82903

Tool/software:

Hello Teams

We are using TPSM82903SISR as shown in the attached image we are not getting required current (3A) at the output when cable length is 30 meter (23 AWG), but when we using 1-2 meter cable it is working fine.

What could be the reason.

Best Regards

Abhineet Ranjan

5 months ago

0 David_Daniels 5 months ago

TI__Mastermind 23775 points

Hello Abhineet,

I am not assigned to this device but I think I can help.

The 23AWG wire has a resistance of 0.0668 ohm/meter according to a reference guide, so for 30 meters the resistance of the cable is 2ohms.

So, if you pulling 3A, the voltage is probably dropping,

For the 2m cable test, what is the voltage on the end. It should be equal Vsupply - Iload*Rcable

Best Regards,

David

0 Abhineet Ranjan 5 months ago in reply to David_Daniels

Intellectual 635 points

Vsupply is same as 30m.
Test Input case is same for both the wires.

Best Regards
Abhineet Ranjan

0 David_Daniels 5 months ago in reply to Abhineet Ranjan

TI__Mastermind 23775 points

Check the voltages at node A, B and C with 30m and 2m wires.

The resistance of the 30meter line is about 2ohms.

Attempting to draw 3A on 30 meter yields a voltage drop greater than the dc dc supply voltage.

Vdrop=Icurrent*Rcable

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TPSM82903: Transmiting power over 30 meter (23AWG cable)