I have theoretical understanding of general electronics basics, however I do not have any practical experience in circuit design. Therefore I need some advice of what would be the best practice on how to set up a circuit that has some requirements.
I have multiple industrial cameras that are triggered by one master camera. The master camera has an internal mosfet and the slave cameras are triggered by an internal optocoupler. Furthermore the trigger event should also go into a MARK_IN pin of a gps receiver which has an 3.3V high and 0.0V low level and registers the triggering event on a falling edge.
I set up a basic circuit in a simulation that I can think of that is shown below:
Here the 820 ohm resistors with the diode (led) are the internal trigger_in optocouplers of the slave cameras. The mosfet is the trigger_out when an image is taken by the master camera. Furthermore I thought about connecting the MARK_IN pins of the gps receiver like shown (I do not know how the internals of the MARK_IN pin looks like, datasheet only say it should be 3.3V with falling edge).
However, with my design I see a lot of problems:
- The voltage level does change at MARK_IN when the number of connected slave cameras changes. For example just one slave instead of 2.
- The energy consumption is about 150mW when the mosfet pulls the line on ground, which I think is quite a lot.
So I am wondering if there is a typical approach how to realize such circuit? That can handle a varying amount of slave cameras and still keeps the MARK_IN pin on 3.3V level. Am I on a right track or completly wrong? And furthermore, a circuit that is more energy efficient.
Apart from that is there anything wrong with my circuit in general, or something that I am missing?