I am trying to set up a current limiting circuit in my design and have set-up the following using an TIP 127 and an MPSA 56 (gotten this particular circuit on the web).
I am using two 9V batteries in parallel (line on the left of the diagram), as I am powering a step motor (center taps, line on the right of the diagram). When I place any load on the circuit, it is meant to act as a chopper circuit and limit the current going to motors (by switching off the supply).
In practice, it completely eliminates any power to the motor (checking voltage with a volt meter), when any load is applied. Does anyone have any insights as to what I am doing wrong?
Thanks for your help
I am using two 9V batteries in parallel (line on the left of the diagram), as I am powering a step motor (center taps, line on the right of the diagram). When I place any load on the circuit, it is meant to act as a chopper circuit and limit the current going to motors (by switching off the supply).
In practice, it completely eliminates any power to the motor (checking voltage with a volt meter), when any load is applied. Does anyone have any insights as to what I am doing wrong?
Thanks for your help