Hi, I am trying to build the circuit in Figure 1 in this link:
I want to get Vw= 0.4V or higher (0.4-0.8 V). Rw has a small value between 4-8 Ohms. The idea of the circuit that when an air flow goes by the hot wire resistance Rw, the hot wire resistance decreases, while keeping the voltage constant across Rw (Vw should stay constant).
My problem is to choose an Op Amp that will keep the voltage constant across Vw, while giving an output current of over 80mA. I tried many Op-amps for that matter, even the high output power op amps but nothing works for that design. Would someone help me with that.
Thanks