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Does that help?
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That is a little easier to see
Would it be vp3 out ?
Would it be bout1 & 2missing/deleted image from Google+
I’m getting the same voltage across all of the drivers
They all read 12v
Not sure. Trying to figure this out as we go. Maybe there is someone else that has done this before on your chip and can chime in. I’ve never had to measure the voltage across them. My drivers have digital pots (4E3D board) so I can read the voltage directly from my LCD screen and change it.
I’m pretty certain that you don’t measure directly across the chip itself and the meter should be set to read DC voltage. One lead should go to the power connector ground.
That can’t be right, there are 8 pins on each side
Swap the location of the drivers on the board and see what happens now.
Does this video help?
I may have gotten it, but it’s hard to understand. Part is in German. Here is the post: https://www.my-home-fab.de/en/documentations/technical-descriptions/drv8825-adjust-stepper-current
@George_Allen It’s the current which will vary. The voltage you need to measure is on the driver’s multiplier, not the output voltage.
Based on the title of the video Jeff Parish provided it looks like that’s what you need. There should be a small pot to adjust. Make sure you don’t short anything. You measure voltage between the pot and GND. Adjust the pot until it hits the proper voltage for your specific driver’s chipset. Be warned that some driver sticks have different models which require slightly different voltages.
That seems to match the technique in the video I found. Are the voltages from the center of the pot to the ground the same for both drivers?
Yes it looks like mine should be.7 v, but in the example I looked at the person doesn’t have his (-) on gnd in the photo. Please look.
It’s odd. One is 1.6v and 2 are 4.9v if I’m doing it right
I must be doing something right b/c adjust of pot changed it
Well if the 1.6v is the X driver then that would indicate that it is quite low. I don’t think you need to run yours at 100% at 7 V. 4.9 of 7V is 70% which is a fairly typical setting.
Sounds like you are back on track. 