MPM3695 Ictrl current

In the MPM3695-25 datasheet, Ictrl is shown as 2.5mA in the absolute max ratings, and 1mA in recommended operating conditions. Can you explain those numbers? They are listed as if they are output specs, but CTRL is a “digital input”. I would expect those requirements more in the electrical characteristics section then abs max/recommended areas, so I’m hoping there is some confusion here that you can clean up.

I really need to know if that input pin can really take 2.5mA worst case, as I was planning on feeding it from the open-collector power-good output of another regulator. Also, is the Ictrl number for a MPM3695-100 4-times that of the MPM3695-25?

That number is likely there for just the circumstance you envision. Where the CTRL pin is driven from a high voltage impedance limited signal. The logic level is 2.2V , they don’t tell you it seems what the clamping voltage is, I am guessing Vcc + 0.5V ( about 3.8V) and then you can calculate how much your resistance needs to be. I doubt there is a need to have even 1mA in the normal operating range that should be a high impedance input although the datasheet doesn’t make that at all clear.

Opinion is worth what you paid for it. Do you have a demo board to play with? You should be able to characterize this.

We have the MPM3695-100 eval board so I’m told (presumably EVM3695-100-BH-00A). I haven’t been able to find the schematic for it yet, so if you could provide that, or point me to it, maybe I can characterize it as you say.

Hi woody.johnson,

Thanks for your question.
Please contact MPS NOW Remote Support to get the schematic.
The CTRL current limit for MPM3695-100 should be the same as MPM3695-25 as it is just a digital input pin that turns the regulator on or off.
The absolute maximum for I_CTRL is 2.5mA. This means if you operate outside these ratings you may damage the device.
The recommended operating condition for I_CTRL is 1mA. Meaning the device is not guaranteed to function per the datasheet specs if you operate beyond this rating.

Thanks,
Cindy

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