R
[email protected]
- Jan 1, 1970
- 0
I will be driving a unipolar stepper motor with an old 68HC11. I'm
thinking about using this http://www.aaroncake.net/circuits/stepper.asp)
circuit control the motor so the microcontroller can focus mostly on
sensor input. I've been told I need to isolate the microcontroller
from the stepper coils via optoisolators. I have three, possibly
three questions about this:
1. I'm assuming this means I will need two power supplies, one for
the microcontroller/sensors and one for the steppers?
2. The optoisolators I've looked at don't mention a built-in resistor
in the schematics, do I need to provide one
3. Would I put the optoisolators between the microcontroller and the
control circuit (IE on the clock/step and reverse lines) or would I
need to also isolate the controller circuit (IE place the opto-
isolators between the JK Flip-flops and the power transistors?)
4. If I need to isolate the controller circuit as well, would the
4027 be able to sink the (10ma if I'm reading the 4Nxx spec right)
current from the opto-isolator? I don't see info on maximum power
dissipation on the 4027's spec sheet (http://www.futurlec.com/
4000Series/CD4027.shtml) though I admit I'm no EE.
Thanks in advance!
thinking about using this http://www.aaroncake.net/circuits/stepper.asp)
circuit control the motor so the microcontroller can focus mostly on
sensor input. I've been told I need to isolate the microcontroller
from the stepper coils via optoisolators. I have three, possibly
three questions about this:
1. I'm assuming this means I will need two power supplies, one for
the microcontroller/sensors and one for the steppers?
2. The optoisolators I've looked at don't mention a built-in resistor
in the schematics, do I need to provide one
3. Would I put the optoisolators between the microcontroller and the
control circuit (IE on the clock/step and reverse lines) or would I
need to also isolate the controller circuit (IE place the opto-
isolators between the JK Flip-flops and the power transistors?)
4. If I need to isolate the controller circuit as well, would the
4027 be able to sink the (10ma if I'm reading the 4Nxx spec right)
current from the opto-isolator? I don't see info on maximum power
dissipation on the 4027's spec sheet (http://www.futurlec.com/
4000Series/CD4027.shtml) though I admit I'm no EE.
Thanks in advance!