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Hi All,

I've design this circuit to give me +- 20 mA at the frequency shown. How likely is this to work in the 'real world'. I just wanted to get some input. The characteristics of the signal are not important (cross-over distortion, rise time, etc..).

Um, whatever you tried to include as a picture isn't showing up.

Can you publicise your circuit?

My apologies. It should be visible now.

If you want to drive a squarewave (or a pulse) into a load then you may need a faster gate drive to the MOSFETs. The 741 o/p slew rate is slow enough that there may be unwanted power dissipations in the MOSFETS because they do not turn on and off quickly. They are acting as source followers rather than switches.

Source followers are basically unity gain buffers with a source voltage that follows the gate voltage but with a voltage drop roughly equal to the Vgs_threshold voltage.

Because the source voltage is affected by the Vgs_th voltage, the output into your load will not be well defined. It will vary from device to device.

Using source followers like this does avoid shoot-through current in the MOSFETs as conduction switches from one to the other but it is not a very efficient way of driving a switched current into a load. Look at step down or Buck switch mode supplies with synchronous switches to see how it's done (avoiding shoot through).

Difficult to be more specific without knowing more about what you want to achieve.