methods reducing |VGS| of a mosfet question

[john23]

Hello,As you can see below M1 Vgs is 14V.
I dont need 14V to open this transistor , I need only 5V.
I have extra Vgs, Is there a way to reduce the Vgs?
Thanks.

 

[Salitronic]

If the input voltage is fixed and known you can just add a resistor across C10 to form a voltage divider with R4.
If the input voltage is variable then you can add a 5V Zener diode across C10 to cap the voltage.

You should also add some resistance in series with C10, as it is now C10 will discharge directly into U1 and U2 when their outputs go low, it's quite a large capacitor and the discharge current will damage the comparator output.