LMZ31710 - Right starting point for 4 A load with surge currents of 14 A / 2 ns?

Jonathan Bender

Other Parts Discussed in Thread: LMZ31710, LMZ31520

Hello,

I have a custom ASIC which requires 4 A @ 0.9 Vout from a 12 V source. LMZ31710 seems like a good fit, but there are expected surge current requirements of 14 A / 2 ns.

Is the LMZ31710 the right module to be looking at? Or are there some special considerations I need to make in selecting the DC/DC module due to the surge current requirements?

I see the max datasheet spec for COUT is 5000 uF so that should provide plenty of room for the point of load capacitance, but I know there are tradeoffs increasing COUT past a certain point. I'm trying to maintain good voltage regulation (< 30 mV pk-pk ideally) while still keeping dynamic voltage and frequency scaling (DVFS).

Thanks for the help, and let me know if there is additional information I can provide to help determine if LMZ31710 is the best fit.

Jonathan

over 9 years ago

0 J Arrigo over 9 years ago

TI__Mastermind 28020 points

Hi Jonathan,

The concern I have with this application is that the 14A surge current is close to the over-current of the LMZ31710. Have you looked at the LMZ31520?

Regards, Jason

0 Jonathan Bender over 9 years ago in reply to J Arrigo

TI__Expert 7895 points

Hi Jason,

Thanks for the quick reply. The original design fit within the requirements of one LMZ31710, but as power needs increased it moved to a parallel LMZ31710 (like the X2EVM). I agree that the LMZ31520 is a better fit given the current power requirements.

Thanks for the help,

Jonathan

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LMZ31710 - Right starting point for 4 A load with surge currents of 14 A / 2 ns?