Question about voltage multiplier for opamp

[chaitu2k]

voltage multiplier

i'am using an opamp operating with vdd=2v and VSS=-2V ..iam using swithched capacitor technique to realize a multiply by 2 operation..if my input voltage is 2v ..can the output(2v*2) reach 4v.

 

[Fom]

Re: voltage multiplier

Depending on your OP AMP current consumption you can use external or internal capacitor. Some of LCD controllers use internal charge pump with external capacitors. They can multiply VDD by 5 times.

 

[chaitu2k]

Re: voltage multiplier

the opamp is a two stage fully differential miller compensated opamp with pmos input stage the differential input stage hasa current of 20nA in each branch wheras the output stage has 50nA in each branch will this opamp work?

or else can u suggest an architecture

 

[mag]

Re: voltage multiplier

first you should use vdd>Vout.
if you another input is constant, you can use amplifier with gain(=Vin1).
If two input is not constant,use analog multiply.Pls ref national application an31.pdf(use google to find it).