LM3409HV: CSP, CSN Absolute maximum rating and operation deglitch time

Hirotaka Matsumoto

Part Number: LM3409HV

Hi all

Would you mind if we ask LM3409HV?

<Question1>
The datasheet shows that Absolute maximum rating VIN to CSP / CSN is -0.3V upto 0.3V
So, does it mean Vin to CSP have to be within -0.3V upto 0.3V and Vin(CSP) to CSN have to be within -0.3V upto 0.3V, right?

<Question2>
How much is the operation deglitch time in case of over threshold VCST?
We could not find it on the datasheet.

Kind regards,

Hirotaka Matsumoto

over 6 years ago

0 Clinton Jensen over 6 years ago

TI__Mastermind 25500 points

Hello Hirotaka,

For question 1 that is correct. This should not be a worry in any typical application.

I am not sure I understand question 2. Do you mean leading edge blanking time? If so that would be the minimum on time as specified in the EC table. If not could you please clarify? Thanks.

Regards,

Clint

0 Hirotaka Matsumoto over 6 years ago in reply to Clinton Jensen

Guru 27525 points

Hi Clinton san

Thank you for your reply!

About <Question2>, we would like to know blanking time.
OK, we got that blanking time is equal to the minimum on time.

Kind regards,

Hirotaka Matsumoto

0 Hirotaka Matsumoto over 6 years ago in reply to Hirotaka Matsumoto

Guru 27525 points

Clinton san

About Absolute Maximum Rating of "VIN to CSP, CSN", do you have actual value which the device is broken as the reference?
(For example X.XV@nsec,,,,)
Of cource, the device should be used in Absolute Maximum Rating.
We appreciate your help always.

Kind regards,

Hirotaka Matsumoto

0 Clinton Jensen over 6 years ago in reply to Hirotaka Matsumoto

TI__Mastermind 25500 points

Hello Hirotaka-san,

We do not have an exact spec, but spikes at the edges of the switching waveform are common with any switching regulator. Anything less than about +/-3V for anything less than about 50ns would be perfectly safe. The +/-0.3V spec is for a DC voltage and that includes some headroom for safety. As long as you follow good layout practices the spiking on these pins should never be a worry.

Regards,

Clint

0 Hirotaka Matsumoto over 6 years ago in reply to Clinton Jensen

Guru 27525 points

Clint san

Thank you so much for your help.
OK, we got it.

Kind regards,

Hirotaka Matsumoto

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LM3409HV: CSP, CSN Absolute maximum rating and operation deglitch time