I have a generic laser galvo scanner. I would like to know what voltage i need to feed to it to control its rotation manually.
I have a generic laser galvo scanner. I would like to know what voltage i need to feed to it to control its rotation manually.
+-5V is what they take.
Thnaks, does this mean 0 to 10V can be used or no?
I dont want to connect it to a DAC but a microcontroller which can output 0-5V analog signal. This is what i meant by controlling it manually. I can amp it up to 0-10V but dont know how to convert that to -5 - +5. Any ideas?
You need a correction amp of some sort but I am not sure of the best way to do that. Brute force you could use an opamp but I have to imagine there are more modern ways.
Here's a basic circuit to convert 0-5V to +/-5V. The opamp can be just about anything. Rail-to-rail types will need a supply voltage of at least +/-5V, crusty things like TL0x series will be happiest if supplied something like +/-9V. The resistor values aren't critical as long as they're the same.
As an alternative, if your drivers have differential inputs, you can connect your 0-5V signal to the positive input and connect the negative input to a constant +2.5V. The driver will then see effectively a +/-2.5V signal. Likewise if you have a 0-10V signal, you would connect the negative input to a constant +5V.
Hey thanks. Much appreciated, , looks simple enough.
That said I don't have a +-5V PSU. Any chance a +-12V PSU can be used? Maybe even the one powering the scanner drivers?
Sure, as long as the op amp is spec'ed for +/-12V operation--and that gives you enough headroom for TL07/8x parts which are pretty common.
Just to be clear, though, the +5V reference in that schematic still has to be +5V regardless of what your supply voltage is. You can derive a 5V supply from the 12V supply using a simple 7805 regulator. You might want to add a load resistor to the 7805's output for stability, maybe something like 500R.
Neat. Thank you, didn't expect to get away so easily.
Well I kind of didn't, just realised Arduino's analog out is only 8 bit, will need to find a better mincrocontroller.