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AMC1301: Negative supply?

Y Bertrand
Prodigy 60 points

Part Number: AMC1301

Hi,

I'd like using the AMC1031 for current sensing across a shunt. From the datasheet the supply voltage can be +5V or +3.3V.

The input can go from +/- 250mV. Great.

However I want to be sure... let's say I have -200mV at the input, with a fixed gain of 8.2 I would expect -1.64V at the output.

However since the supply voltages are unipolar positive, I wonder how any negative value can appear at Vout?

Is there a sort of H bridge at the output that can basically invert the voltage to attain a negative supply voltage?

I would like to have some kind of confirmation the amplifier can in fact output negative voltage from unipolar supplies,

and be given precision on how the output stage is made overall (transistor configuration, H bridge for example).

Thanks

  • 0
    TI__Guru**** 182761 points

    Hi Y,

    The AMC1301 has a single supply on both sides of the isolation boundary.  Yes, it can accept -250mV input but the out is a differential voltage riding on a common mode voltage of 1.44V.  With -200mV on the input, the differential output voltage can reach -1.64 (i.e. the VOUTn is higher than VOUTp), but neither the VOUTp or VOUTn will go below ground.