Need a solution for comparator circuit

[cuongbui1702]

I have problem with this circuit. Normally when vP>vN (if I set vN>0.4V), output vQ is equal 5v. But when I set vN < 0.4V, output is not true, it is always 5V not only for vP< vN but also vP>vN. I need to design ADC circuit, and that is comparator block. Need some suggestions. Help me
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I supply V = 5V, vG = 0V, VPbias = 0V

 

[Macie Sawney]

I as well would like to know this...

 

[Svein]

Start with eliminating all but the most basic things. This means removing XM8, 9 and 10. If it still does not work, try increasing V_Pbias. If it still does not work - I am currently out of ideas.