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I have a question about PMOS load driver. When V1 is high then Vout should be 1.5 V and it is okay. But when V2 is high, Vout should be 3 V rather than 2.4 V.

Can anyone explain me why this 2.4 V and how can I fix this? enter image description here

enter image description here

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Can anyone explain me why this 2.4 V

It's because of the body diode inside the M2 MOSFET: -

enter image description here

The 3 volts is fighting to push current through the body diode and can't win.

Can anyone explain me.... how can I fix this?

One option is to use back-to-back MOSFETs as per a solid state relay: -

enter image description here

Picture taken from this question. Back-to-back MOSFETs can handle bidirectional currents: -

enter image description here

Picture from here. Or use a proper power path controller like this chip that also uses bidirectional MOSFETs: -

enter image description here

Image from here.

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    \$\begingroup\$ Sorry i forgot to say thank you. I understand now and decided to use solid state relay. \$\endgroup\$
    – mtoprak
    May 30, 2022 at 6:31

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