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previous: GFR You can try "buffering" the output ... -- 1/14/2000 4:55 PM View Thread

Re: Driving a Lo-Z load with opamps question

1/14/2000 7:25 PM
AMZRe: Driving a Lo-Z load with opamps question
You could set up the opamps so that they push-pull the load to double the output.  
If you parallel the outputs, I would definitely add a resistor on each output as R.G. said. This will help distribute the load because otherwise one of them would dominate and do most of the work.  
"A CMOS inverter can also be used as an output buffer for  
opamps. It won't have as much crossover distortion as a class-B bipolar buffer."
The CD4007 is also good for this - parallel the 3 pairs of transistors to increase output drive.  
With transistor drivers, to reduce crossover distortion, a resistor could be added between the driver output and their input so that the opamp could supply current at low levels before the transistors switch on. This trick is used in the appnotes for the LM379 and related chips.  
Another idea is to use a power opamp. For instance, an LM380 or maybe even the LM386.  
regards, Jack

Ed Rembold Thanks guys -- 1/14/2000 11:41 PM