TPS25947: Designing with TPS259470LRPWR

Part Number: TPS25947

Hello Team,
We are planning to use the IC TPS259470LRPWR for one of our applications.
We had a discussion with the TI team regarding the same. Link.

Following is the circuit of the same.
Can you please review and please let me know if any changes are needed.

The current limit is set to 4A.
The ITIMER is set to 2mS
The pin OVLO is grounded.
The E/UVLO pin will be controlled by a 3.3V MCU

Looking for your reply.

over 1 year ago

0 Kunal Goel over 1 year ago

TI__Guru* 79181 points

Hi SV,

Looks fine. Current limit looks to be 5A not 4A.

Regards

Kunal Goel

0 Sv over 1 year ago in reply to Kunal Goel

Intellectual 585 points

Hello Kunal,
Thank you for your reply.
Can you please look at the below calculation?.

5.2. Calculating the Current limiting resistor Value

I_LIM (A) = 4A
R_LIM (Ω) = 3334/4 = 833.5Ω

Looking for your reply.

+1 Kunal Goel over 1 year ago in reply to Sv

TI__Guru* 79181 points

Yes ..it if fine. I was reading 8 as 6.

0 Sv over 1 year ago in reply to Kunal Goel

Intellectual 585 points

Hello Kunal,
Ours is a 5V systems and our load is a set of LEDs.
Do we need the following diodes.

The diode we are using now are BAT54WS-7-F and CDSOD323-T12SC.
Can you suggest diode for 5V system?

0 Kunal Goel over 1 year ago in reply to Sv

TI__Guru* 79181 points

You can remove these external diodes.

0 Sv over 1 year ago in reply to Kunal Goel

Intellectual 585 points

Hello Kunal,
Thank you for your reply.
The protection diodes are needed only when we have an inductive load.
Can you please explain these diodes protect during transients?.
How to select the voltage of the diode if I have an inductive load like a 5V motor?

Looking for your reply.

0 Kunal Goel over 1 year ago in reply to Sv

TI__Guru* 79181 points

Hi Sv,

These diodes are needed for below purpose:

If you choose to use them you can pick such that it clamps below 21V.

Regards

Kunal Goel

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TPS25947: Designing with TPS259470LRPWR

5.2. Calculating the Current limiting resistor Value