TPS62065　tStart

K.Hamamoto

Guru 12155 points

Other Parts Discussed in Thread: TPS62085, TPS62065, TPS62065-Q1

Our customer would like to know the variation of start up time for this device.

The variation is specified as tStart on the datasheet. However there is no min and max value.

Can you provide that min and max value? It may depends on Iout and Cout and some other components.

Regards,

Koji Hamamoto

over 8 years ago

0 Chris Glaser over 8 years ago

TI__Guru*** 142880 points

This is not specified. Note that by looking at the figures and reading the description, this 500 usec is actually a ~250usec wait time after EN goes high and a ~250 used ramp time. Yes, if too heavy a load or excessive a Cout is present it will reach current limit and lengthen the time.

I would also recommend a DCS-Control device such as TPS62085 instead. It has better efficiency as well.

0 K.Hamamoto over 8 years ago in reply to Chris Glaser

Guru 12155 points

Hi Chris-san

Thank you for your support.

As you mentioned, tStart = tWait(typ:250us after EN on) + tRamp (typ:250us).
The tRamp may be depended on Cout. How much the max valu of the tWait?

Our customer would like to estimate the maximum value of tStart.
Because it is required from end customer.

Regards,
Koji Hamamoto

0 Chris Glaser over 8 years ago in reply to K.Hamamoto

TI__Guru*** 142880 points

There is likely no characterization data for this parameter, but double might be an estimate at a potential maximum value.

But I would rather understand what the customer's real concern is. Do they have inrush current restrictions? Do they have startup sequencing requirements? Do they just need a value for some production test parameter?

0 K.Hamamoto over 8 years ago in reply to Chris Glaser

Guru 12155 points

Hi Chris-san

Thank you for your support.

The customer is required the estimating of startup time from end-user.

Regards,
Koji Hamamoto

0 K.Hamamoto over 8 years ago in reply to K.Hamamoto

Guru 12155 points

Hi Chris-san

We got additional question from customer.
Could you provide a minimum value of tstart? (an estimate at a potential minimum value.)

Because they have an problem for some sequence which is depended on the output timing of TPS62065.
They would like to estimate a variation of output delay. (Min/Max)

Regards,
Koji Hamamoto

0 Chris Glaser over 8 years ago in reply to K.Hamamoto

TI__Guru*** 142880 points

Could you please list the power requirements which TPS62065 fulfills? It would seem better to use a device which meets your spec. Do they need -Q1? If there is some specific startup time needed, please describe it.

0 K.Hamamoto over 8 years ago in reply to Chris Glaser

Guru 12155 points

Hi Chris-san

I apologize for the delay in replying to you.

TPS62065-Q1 has been already in customer production.
The customer would like to know how much the variation of output delay.　

Regards,
Koji Hamamoto

0 K.Hamamoto over 8 years ago in reply to K.Hamamoto

Guru 12155 points

Hi Chris-san

This question comes from end customer.

Can we estimate the half of the typ value as minimum value?

Regards,

Koji Hamamoto

0 Chris Glaser over 8 years ago in reply to K.Hamamoto

TI__Guru*** 142880 points

Yes, this would be an estimate but it's still better to know why they care about this parameter.

Power management

Power management forum

TPS62065　tStart

Power management

Power management forum

TPS62065 tStart

TPS62065　tStart