I'm working on a biomedical project, and need to transfer power from a non-ideal source, with a very high internal impedance (~700Kohm) and low voltage, to a load with a high impedance (~1Mohm). I need to maximize the voltage delivered to the load, and because the source has a high internal impedance, I need to have a buffer between the source and the load. Would an op-amp based voltage follower do the job (non-inverting with gain = 1)?
Also, because of the design limitations, I'm trying to find the right op-amp. The priorities are: 1- It must have a low power consumption, 2- It must have a high input impedance, 3- It has to have a low vcc.
I found this from TI http://www.ti.com/product/lpv821 , which seems to satisfy my constraints.
To summarize, my questions are:
1- Is a voltage follower the right circuit? 2- Is the above op-amp suitable for this purpose? Thanks!
The input source is a low frequency AC signal (less than 1khz) and no DC. The peak to peak input voltage is less than 2.5V and I'm hoping to transfer the same to the load.
The maximum voltage to power the op amp would be 5V (2.5V for positive supply and -2.5 for negative) but the input wont be more than 1.25 in anplitude.
The circuit is meant to work in room temperature.