TPS7A20: Inrush current of 1.2A

Dice-K

Part Number: TPS7A20

Tool/software:

Hi support team,

5.2V is input to the TPS7A2050PDBVR to generate 5V.
The current value was measured when an inrush current occurred in the circuit to which it was supplied.

(CH1: Input voltage CH3: Output current)

According to the datasheet, the current limit is set at approximately 360-700mA,
but it appears that about 1.2A flows at the moment of inrush and then the limit is set.
Is this correct behavior?
Also, if it is correct, is this inrush current value acceptable for the device?

Regards,
Dice-K

6 months ago

0 Alex Davis 6 months ago

TI__Genius 12010 points

Hello Dice-K,

I'm looking into this and will provide an update in 1-2 business days.

Best Regards,

Alex Davis

0 Dice-K 6 months ago in reply to Alex Davis

Mastermind 7460 points

Hi Alex,
I appreciate your assistance.

I look forward to receiving updates on the investigation.

Best regards,
Dice-K

0 Dice-K 6 months ago in reply to Dice-K

Mastermind 7460 points

Hi Alex,
Does it still take a while?

Is it possible to avoid the delayed response of current limits below 200us?

Best regards,
Dice-K

0 Dice-K 6 months ago in reply to Dice-K

Mastermind 7460 points

Hi Alex,
How is the situation?

Please let me know the current situation, even if it's just in progress.

Best regards,
Dice-K

0 Dice-K 6 months ago in reply to Dice-K

Mastermind 7460 points

Hi Alex,

Is this question difficult to answer?

Best regards,
Dice-K

+1 Alex Davis 6 months ago in reply to Dice-K

TI__Genius 12010 points

Hi Dice-K,

I apologize for the delayed response. After discussing internally, I can confirm this behavior is normal. The current limit circuitry will take a small amount of time to activate and limit the current to the steady-state value listed in the datasheet.

If a soft-start pin or external feedback network was available, inrush could be reduced by slowing the turn-on time of the device, however TPS7A2050PDBVR does not provide either of these options.

Best Regards,

Alex Davis

0 Dice-K 6 months ago in reply to Alex Davis

Mastermind 7460 points

Hi Alex,
Thank you for your reply.

The current exceeds 520mA for about 140μs.
Isn't this liable to cause damage to the device?

Best regards,
Dice-K

+1 Alex Davis 6 months ago in reply to Dice-K

TI__Genius 12010 points

Hi Dice-K,

While the current exceeds 520mA, it does so for a short enough time that the device will not increase in temperature enough to cause damage.

Best Regards,

Alex Davis

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TPS7A20: Inrush current of 1.2A