I am new to this forum, so may be getting things wrong. I am trying to identify the characteristics of two transistors (pre-amp and control transistor) in a circuit that has a supply voltage of 0.8 to 1.1 volts and a desired current control range of 100-1000 mA. I am inserting the circuit I have drawn but cannot find a transistor to fit the design. Any leads to this would be helpful.

 

What is the surrounding circuitry like ??
Or is this a classroom problem ??
Are you trying to learn I-C Engineering ??
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If the supply is only 800mV, the voltage drop across the 1N5817 Schottky diode won't allow enough current to flow in the transistors. Why do you have that diode?
Is your circuit perchance intended to modify the output of an oxygen/lambda sensor?