TPS2549-Q1 Vout Absolute Voltage

Kuramochi Tadahiko

Guru 28715 points

Other Parts Discussed in Thread: TPS2549

Hi,

It is mention that absolute voltage of Vout is -0.3V~7V on the datasheet.

However, it seems taht the Vout is less than -0.3V on figure 25.

I think that it can't be admitted.

Is this recognization wrong?

Thanks,

Kuramochi

over 10 years ago

0 Eric Wright over 10 years ago

TI__Mastermind 42795 points

We will check on this figure to see if the measurement was taken correctly. You are correct that Vout should not go below 0.3V as it may damage the device.

0 Kuramochi Tadahiko over 10 years ago in reply to Eric Wright

Guru 28715 points

Wright-san,

Thank you for your help.

My customer is very hurry, so the quick response is helpful for them.

Regards,

Kuramochi

0 Eric Wright over 10 years ago in reply to Kuramochi Tadahiko

TI__Mastermind 42795 points

Here is the reply from the TPS2549 systems engineer:

This test condition is, no output cap, using a short cable hot-short to GND, internal power switch fast off, the parasitic inductance would force the OUT pin see some undershoot, if add some output cap would reduce the undershoot with very short time like 2us, all our power switch have this behavior because of fast turn off.

Also, it appears that the voltage scale in the datasheet is wrong. It should be 2V/div and not 2.5V/div.

Basically with the required USB specified VBUS capacitance the undershoot will not be that severe.

0 Kuramochi Tadahiko over 10 years ago in reply to Eric Wright

Guru 28715 points

Wright-san,

Thank you for your quick help.

I would like to confirm following.
>Basically with the required USB specified VBUS capacitance the undershoot will not be that severe.
Does it mean "If capacitors are connected to VBUS, satisfied specific of USB is not severe basically."?

Best Regards,

Kuramochi

0 Kuramochi Tadahiko over 10 years ago in reply to Eric Wright

Guru 28715 points

Hi Eric-san,

My customer requires to confirm whether there is another wrong point in this datasheet?

Could you confirm it ?

Best Regards,

Kuramochi

0 Eric Wright over 10 years ago in reply to Kuramochi Tadahiko

TI__Mastermind 42795 points

Hi Kuramochi-san,

Can you tell me which point you are referring to in the datasheet? Please specify page # and section.

0 Kuramochi Tadahiko over 10 years ago in reply to Eric Wright

Guru 28715 points

Hi Eric-san,

Thank you for your quick help.
My customer requires all pages.

Thanks and Regards,
Kuramochi

0 Eric Wright over 10 years ago in reply to Kuramochi Tadahiko

TI__Mastermind 42795 points

Hi Kuramochi-san,

I am not understanding the question. Is your customer asking "are there any known errors in the datasheet"?

My reply is no but I will check with the systems team to see if there are any planned changes or updates to the existing online datasheet.

0 Kuramochi Tadahiko over 10 years ago in reply to Eric Wright

Guru 28715 points

Hi Eric-san,

>Is your customer asking "are there any known errors in the datasheet"?
No, the customer requires to be checked the datasheet over again.

> I will check with the systems team to see if there are any planned changes or updates to the existing online datasheet.
It is helpful for them and me.
I appreciate your support.

Thanks and Regards,
Kuramochi

Interface

Interface forum

TPS2549-Q1 Vout Absolute Voltage