TPS62816-Q1: TPS62816 risk

BTW， 

the waveform recorded when our device start up with output short to GND

Hi Eric, 

I do not see a concern with it unless the ABS max rating of the pins are excedeed. 

Please make sure that the test/verification does not violate Abs max rating of the device.

Thanks and best regards

Sneha 

Hi Sneha,

Does the SW voltage can not exceed the (-3V) less than10ns

Hi Eric,

No, I would not recommend doing so. Marginally exceeding Abs max rating might not fail the device immediately, but it could degrade the device's performance and affect its lifetime.

Thanks!

Best regards

Sneha 

Hi Sneha,

I want to know what will happen if we add a higher voltage source to the TPS62816 Vout? could you pls give some analysis for this

Hi Eric, 

Do you mean Vout is higher than Vin?

The device would not regulate under such cases.  If the device would be in FPWM, this could force a current to flow through the body diode of the IC, hence damaging the FETs. 

Thanks!

Best regards

Sneha 

Hi Sneha,

my means is that if we inject an external voltage source into the TPS62816, what will happen?

One more question,

We often use the transfer function to judge the DCDC loop stability, but the transfer function applicable for the LTI system , if our DCDC works in the PFM or PSM mode , can we think it still is a LTI system? if no, how can we know the system stability in PFM mode?