Just saw this and I have also looked into using the OPA445 as part of an amp build. Take a look at the SSA35, SSA120 amps at by-rutgers dot nl which are also referenced in this post
Power Amplifier with Small Signal OP-Amp in the Front-End - Overview wanted
Power Amplifier with Small Signal OP-Amp in the Front-End - Overview wanted
I find OPA453 has better bandwidth in circuit.Has anyone used the OPA445 as the "driver" in a power amp? What voltages did you feed it? The datasheet says abs. max 50V each rail, and I was thnking of feeding it 48V each rail so as to make a 200W/4R audio amp!
OPA453 can take +/- 40 Volt supply.
But as I said, you get better frequency with OPA453.
OPA453 can deliver 50mA and it is one TO-220 capsule.
http://www.ti.com/lit/ds/symlink/opa452.pdf
Here is one example of using OPA453 as power amplifier.
Give it a try.
You have a DC gain of 18 as well AC gain of 18.
Most power amps use DC gain of 1 to keep them more stable during temperature change.
I would have used an AC coupling capacitor and resistor to ground on input to set GND level.
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Here is one example of using OPA453 as power amplifier.
Give it a try.
I would think that a single pair of outputs would work at that voltage, unless I’m missing something?
Nice simple circuit!
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