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The question is concerned the output current of push-pull amplifier once the over-current protection is activated. The resistor Rs(one between base and emitter of the over-current protection transistor T) has it's resistance so that Vbe=Rs*Ipmax. So when the current reaches Ipmax, it turns on the transistor T, and transistor T pulls some of the current from the regular transistor. My question is: does the current on the load stay Ipmax, after the protection turns on, and if yes, can it be calculated analytically?

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If I understand well, we want to have the same current at input and output before and after the protection turns on, so it's quite easy to calculate the current that goes through the protection-transistor, that is if I'm right with the statement that currents on input and output stay the same.

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    \$\begingroup\$ What input and what output - be precise. \$\endgroup\$ – Andy aka May 20 '18 at 13:53
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Yes. Once the current exceeds the threshold the limiting transistor turns on and the voltage across the sense resistor is kept at 0.7 volts, meaning the output current is constant.

In the future please give a schematic with reference designators. It makes it much easier to talk about the circuit.

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