Camera motor control

Hi

i was hoping someone can help me. i have attached a pdf to this post. the pdf shows a camera lens i have, including the wiring diagram. i was hoping someone could help me detemine the best way in which i could control this motor, also if possible to expalin how the wiring works. the wiring diagram shows switches attached to it, so i am a bit confused. would a H bridge work, as i now they are dc motors working at 6.4v

Thank you

HD1166R(1).pdf (111 KB)

The wiring shows two switches per motor. Nothing complicated. The diodes probably take care of unwanted noise around the operating switches. The switches probably need to be of the kind that doesn't allow both to be pressed at the same time. I don't see why an H-bridge wouldn't work here. What are you planning to do with it?

No no no, the diodes are nothing to do with noise!

This is a completely standard limit-switch circuit, each limit switch is normally closed, but opens when the limit is reached, cutting off the current to the motor only if its travelling towards the limit. The diodes allow the motor go the other way, back from the limit, even though that limit switch is open circuit.

The circuit has boxes marked "NFU" - not knowing the function of these its hard to say how to drive these, I suspect the abbreviation is for "N??? Focus Unit", and it may be these have some electronics, or may just be names for the sets of wires.

If they are just names you simply apply 6.4V or thereabouts to a pair of wires and the motor will move until the endstop and stop. Reverse polarity and it moves back to the other endstop and stops. The motors are very low current, note, 40mA rated (stall current will be more of course, as always).

If the NFU boxes represent some active circuitry it may complicate things. I'm not sure what circuitry this could be.

MarkT: No no no, the diodes are nothing to do with noise!

This is a completely standard limit-switch circuit, each limit switch is normally closed, but opens when the limit is reached, cutting off the current to the motor only if its travelling towards the limit. The diodes allow the motor go the other way, back from the limit, even though that limit switch is open circuit.

The circuit has boxes marked "NFU" - not knowing the function of these its hard to say how to drive these, I suspect the abbreviation is for "N??? Focus Unit", and it may be these have some electronics, or may just be names for the sets of wires.

If they are just names you simply apply 6.4V or thereabouts to a pair of wires and the motor will move until the endstop and stop. Reverse polarity and it moves back to the other endstop and stops. The motors are very low current, note, 40mA rated (stall current will be more of course, as always).

If the NFU boxes represent some active circuitry it may complicate things. I'm not sure what circuitry this could be.

Hi

Thank you for that the H Bridge worked perfectly. However is there a way in which I could use the two wires for each motor, to determine its position. For example when it has reached the end of one end of the motor and the end of the other motor, also in between. What kind of circuit would I need to build, or would I physically need to open the camera, and then use the internal switches.

Thank you

You could sense the current, which will fall to zero at a limit.