[SOLVED] Getting an output voltage from the op-amp more than the supply voltage

[Elex-factor]

I want to use MAX44262 as a voltage amplifier. I am using a solar cell as a supply voltage which will be 2V. My question is can I use the same solar cell voltage as an input to the op-amp and amplify it to 3.5 V. I read somewhere that the output voltage of the op-amp can not go higher than the supply voltage. So, is it possible? If not, what might be other alternatives to amplify the 2V output of the solar cell without using any external power supply? Please help....

 

[pwdixon]

You could try using a booster to produce a higher voltage supply and then use that to supply the amplifier.

 

[FvM]

It seems like you are confusing amplifiers and voltage converters.

 

[crutschow]

You would need a boost type switching regulator.

 

[Elex-factor]

You could try using a booster to produce a higher voltage supply and then use that to supply the amplifier.

Can you please suggest me some booster types? And also i wanted to ask, doesn't the booster need any power supply? The problem is that I can not use any external power supply. Please help...

 

[pwdixon]

Can you please suggest me some booster types? And also i wanted to ask, doesn't the booster need any power supply? The problem is that I can not use any external power supply. Please help...

The actual circuit depends on the power requirement.
Look at MC34063 they are easy to setup and cheap.

 

[Elex-factor]

The actual circuit depends on the power requirement.
Look at MC34063 they are easy to setup and cheap.

Thank you for the help. Actually MC34063 operating voltage range is from 3 V to 40 V which does not meet my requirement because the output voltage from the solar cell is only 2 V. So I checked the booster from the same company and found NCP1410. I think it'll meet my requirement.

 

[FvM]

MC34063 doesn't work below 3V input voltage. There are special boost converter ICs from major vendors like TI or Linear that support lower input voltages. A simple switched capacitor voltage doubler might also work for you, particularly for low low currents. Which current is available from your solar cell?

I presume you are aware of conversation of energy law, means tht converter can't output more power than given to it, minus internal losses.

 

[godfreyl]

An energy harvesting chip, like one of these may be a good solution. e.g. The LTC3105 works with an input voltage as low as 0.25V.

 

[Elex-factor]

MC34063 doesn't work below 3V input voltage. There are special boost converter ICs from major vendors like TI or Linear that support lower input voltages. A simple switched capacitor voltage doubler might also work for you, particularly for low low currents. Which current is available from your solar cell?

I presume you are aware of conversation of energy law, means tht converter can't output more power than given to it, minus internal losses.

The current from the solar cell is as low as 10 mA. I hope the loss after the booster won't be too high. I think the LTC3105 booster is good for my case.

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An energy harvesting chip, like one of these may be a good solution. e.g. The LTC3105 works with an input voltage as low as 0.25V.

Thanks for the help. I think it'll be suitable in my case.