In fact, I am quite sure I had some professional equipment using such OP-AMPS and it was quite a pain to find them as a spare parts. Defenetely they don't look DIY friendly.
Good hint anyway, thank you.
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If the transducer is a piezoelectric element, expect it to be a pure capacitor (low impedance current sucker) except near resonance, where it will display the usual resonant circuit peak/dip impedance curve. Potentially a tough load for conventional amplifier designs. Most people use an inductor and operate them as resonant tanks, or some variation thereof.
knowing the load is a ultrasonic transducer is a start - already changes estimates of load – from the V alone we can assume a piezo type - there are magnetostrictive transducers too
even among the piezo there are ceramic and plastic, wideband, narrow, launching waves into air, water or moving mechanical structures with struts, stacks, benders - sometimes requiring DC response to hold a deflection
the more you can tell about the application the better our ability to recommend appropriate circuits - what frequency response? pulsed, continuous, DC? - are you really power constrained - battery? or is it a desktop/lab experimental apparatus
even among the piezo there are ceramic and plastic, wideband, narrow, launching waves into air, water or moving mechanical structures with struts, stacks, benders - sometimes requiring DC response to hold a deflection
the more you can tell about the application the better our ability to recommend appropriate circuits - what frequency response? pulsed, continuous, DC? - are you really power constrained - battery? or is it a desktop/lab experimental apparatus
What kind of rails and trafo will you use?
Is it important that output is 100Vp?
What about rails on 100VDC and output 90Vp?
IRF710, IRF720, IRF740 are all 400VDS N-MOS devices.
It would be possible to build an N-Channel amplifier using them
and have rails +/-200 VDC
+/-200 is nothing to be afraid of. Tube people do it all the time.
Is it important that output is 100Vp?
What about rails on 100VDC and output 90Vp?
IRF710, IRF720, IRF740 are all 400VDS N-MOS devices.
It would be possible to build an N-Channel amplifier using them
and have rails +/-200 VDC
+/-200 is nothing to be afraid of. Tube people do it all the time.
I have made a circuit with IRF710, one 400VDS MOSFET.
As there is no such P-Channel device, it is a quasi push-pull with help of one BJT, 2SA1381. 2SA1381 is one 300Volt video transistor.
VAS, voltage amp stage is a bootstrap as we have no suitable P-Channel MOSFET for this.
We get one bootstrap N-Channel amplifier.
Upper -3dB is like 9 MHz. See diagram 1.
The amplifier at 200Vp-p output!!!
gives only THD 0.002%
See diagram 2.
As there is no such P-Channel device, it is a quasi push-pull with help of one BJT, 2SA1381. 2SA1381 is one 300Volt video transistor.
VAS, voltage amp stage is a bootstrap as we have no suitable P-Channel MOSFET for this.
We get one bootstrap N-Channel amplifier.
Upper -3dB is like 9 MHz. See diagram 1.
The amplifier at 200Vp-p output!!!
gives only THD 0.002%See diagram 2.
Attachments
Made a circuit in SPICE. Is a correct language.
But this you understood, didnt you?
You are just out to tease. Why not comment on the circuit.
There must be a few details to critisize.
Every build of a circuit begins with exploring options.
My circuit is to help newvirus with ideas for a project.
And this is what posters should do.
But this you understood, didnt you?
You are just out to tease. Why not comment on the circuit.
There must be a few details to critisize.
Every build of a circuit begins with exploring options.
My circuit is to help newvirus with ideas for a project.
And this is what posters should do.
I don't know how you generate a frequency sweep with your sim program.
Or you could try a number of frequencies at max power: 100K, 200K, 400K, etc and see when the amplitude begins to fall.
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