MMPF0100 PMIC - VTT Rail

[davidkearney]

Hi There,

I'm planning  on using the MMPF0100 as the PMIC for a Zynq Z7020-based design. AN4991 has a useful reference design for this application, I just have once concern regarding VTT, the DDR3 active termination rail. This rail needs to Source and Sink current during DDR3 activity, and I don't see this explicitly addressed in the datasheet. It mentions that SW4 has a VTT mode which tracks V_DDR3/2, but in this PWM mode does it also successfully sink the required current? 

Many Thanks in advance,

Dave

[reyes · Accepted solution]

Hi Dave,

Yes, regulators of the MMPF0100 have a strong sourcing capability and sinking capability in PWM mode, therefore, in VTT mode SW4 works only in the PWM mode to enable it to source or sink load current.

This can be found as a comment in section 4.7 of the application note AN4714.

Have a great day,
Jose

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