kekked:
wont this cut the resolution in half?
No.
The number of steps remains the same (dependent on your DAC) and the resolution (size of steps) doubles as you double the total range.
i cant use the stock 15V dual rail PSU as its huge for this project and theres already a 12V PSU used by other components. I can get 15V from 12 though.
bump
kekked:
i cant use the stock 15V dual rail PSU as its huge for this project and theres already a 12V PSU used by other components. I can get 15V from 12 though.
A "huge" power supply and two amplifiers on a heatsink is a clue to what power is needed to drive these galvanometers. 12volt/1A and -12volt/0.5A = 18watt.
15volt is optional.
Leo..
Those motors rotate at some impressive speeds, so fast they can draw a vector graphic with 4-8 english letters by moving a single laser point so fast it appears as a line drawing to us because of persistence of vision.
I'm just using it for beam steering at much much slower speeds. Even then at those highspeed rotations the heatsinks barely get warm.
In any case Im wondering how to get a -15V from a 12V PSU and not have to use the large dual rail +- PSU here. I got the idea of getting a -5V to 5V signal via DAC but don't how what to do for 12V to 15V power.
15volt is optional
What do you mean?
These don't seem to handle the max current needed ( 12volt/1A and -12volt/0.5A )
±15V :
Input voltage DC 3.3~ 13V,output DC ±15(Deviation is ±4%)
Maximum input current 1.8A
Maximum output current : +Vo is 600mA,-Vo is 120mA
Wawa:
Are you going to use that driver board that comes with the galvo motors.
I think you must, because you need a lot of drive power to get them quickly into position.If you use that board, then you have a dual rail supply available for a 0-5volt DAC to +10/-10 volt converter.
That voltage converter can be made with a common opamp and three resistors.DAC to the + input via ~2k2 resistor.
5volt DAC supply to the (-)input with R.
2R resistor from (-)input to ground.
2R resistor from (-)input to opamp output.R could be 1-5k, so 2R could be 2-10k.
Leo..
Can you please tell me the resistor values and what opamp to use if the PSU will change to a +-12V PSU?
And any recommended 0-5V DACs that are known to work with Arduino would be very much appreciated.
And any recommended 0-5V DACs that are known to work with Arduino would be very much appreciated.
AFAIK, the MCP4922 works fine.
How many steps can a 12 bit DAC provide?
12 bits = 2^12 = 4096