Hello All,

I am using LM358n for amplifying the the voltage and i am taking a 5 volt from arduino and giving to opamp as noniinverting amplifier and i am giving 12 volt to amplifier(+- ends). Using the formula Vo= (1+r1/r2)Vin. But my output voltage is restricted to 6 volts and 35 milli amps. i dont know what is wrong happening.
I need 20 milli amps and 10volts
Could you please help me out.
Thanks
Siddharth

 

hi sid,
When you say 12V to amp +/-V, is that 12V across the amp power pins.?
Or +12V to amp+ and -12V to amp-.?
E

EDIT:
Looking at the LM358 Vout versus Iout curves,shows a fast drop off in Vout for >20mA Iout.

 

2V to amp

I am giving input voltage of 5 volt to + (input ) and ground to - (input).
And 12volt from an adpater to opamp V+- pins .

 

I am giving input voltage of 5 volt to + (input ) and ground to - (input).
And 12volt from an adpater to opamp V+- pins .

But you are trying to draw more current than the LM358 can supply.

 

Could you please help me out.

Post a schematic showing the load.

 

You can use an NPN transistor to boost the output current, something like this :-

 

Is the minus side of the power connected to common, as it should be?

 

See

 

hi Bord'
Your attachments are reporting an 'Error'
Eric

 

hi Bord'
Your attachments are reporting an 'Error'
Eric

Thank you, ericgibbs.