sigle node voltage from two node

[arsal_uet]

i am designing a circuit.
the problem is i want to make the potential difernce between two points which hav some varrying voltage to some commmon constant level of voltage.can u guice me how.
consider the case below:
in my ciruit:
the potential difference bw two supposed points a and  b is in notnal stat:1.435volts
the potential differnce bw the same points considered during excitation is about :1.28 volts to 1.60 volts
now tel me how can i make the varrying difference corresponding to one constant level,that is whenever i got the varrying output during excitatoin above 1.430 volts i got some constant value like 5 volts. plz guide.

 

[AN920]

I am not sure I understand the problem but you can use a comparator to switch high to 5V when the level of 1.43 volts is exceeded.

 

[arsal_uet]

i have already tried what u suggested but problem is the ouput is still varying and i require a constant 5volt dc level.is there any ic which can give me a constant level of voltage even two volts or in other words is ther any ic which give a regulated DC voltage of 2 or 1.7 volts volts for the varrying 1.23 to 1.5 volts

 

[AN920]

Post your circuit cause you must be doing something wrong.

 

[arsal_uet]

ok u willl see it tomoroe.ok.