The principle of the converter similar to a compensation voltage. DA1 exemplary chip compares the voltage to the noninverting input with resistor divider R1-R3 with the voltage coming to the inverting input from the output device. According to the corrected output signal, which regulates unlocking / locking of the output transistors. The maximum voltage is limited only by the supply voltage operational amplifier. A current output – set output transistors. Such is the useful thing.
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