Stripboard stepper driver carrier board

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Stepper driver board

I haven't ordered one of the stepper driver shields, so instead I've designed a stripboard layout to assist with the wiring. I will use solder posts to connect wires to the board.

  • NOTE 1: I found that I have to set $7=200 in the Grbl settings to get the motors to move in the right directions.
  • NOTE 2: This design has been tested with a ShapeOko.
  • NOTE 3: It appears that some electrical noise is being picked up during the first second or two after resetting the Arduino. I'm guessing that during this brief period, the Arduino pins haven't been switched to outputs, so they're high impedance, making the stepper driver inputs more susceptible to noise. I have adjusted the design by changing the pull-down resistor attached to the !enable inputs into a pull-up resistor instead, and this appears to have resolved the problem.
  • NOTE 4: I have added an adjusted board layout with better power supply isolation - see below.

The 47uF capacitors are a bit larger than I'd guessed, so the ground bus-bar had to take the scenic route on my board. I've adjusted the design to allow more room so that others don't have that problem.

Updated version

Here is an updated version with better logic/motor power supply isolation and better motor current handling. Warning: this design is untested.

You will need two 0.1uF ceramic capacitors in addition to the three in the parts list below.

The wires that run parallel to the tracks on the track side have been added to carry the higher motor current, and could be actual wires or just a thick coating of solder.

Parts list

Item Qty Notes Source
Stripboard, 27 strips of 18 holes long 1 stock
Header pin socket row, 24 holes long 2 I cut down a 40-way socket Ebay, not great quality so I won't link to it
Solder pins 23 I used header pins see above
Pair of header pins 9 see above
Header pins, for plugging in to Arduino 9 1x row of 6, 1x pair, 1x individual see above
Jumpers for header pins 9 If not using 16x microstepping then you'll need less! Maplin code N23AN, http://www.maplin.co.uk/2.54mm-0.1-inch-miniature-pin-jumpers-34146
Solid wire for “bus bars” ~40cm low current, so thin is ok stock
10K resistor 1 stock
47uF 50V electrolytic capacitor 3 A lower voltage rating would be ok (>= motor voltage) Maplin code VH33L, http://www.maplin.co.uk/radial-electrolytic-capacitors-13472
0.1uF ceramic capacitor 3 marked 104K stock
Polulu A4988 stepper driver carrier, and header pins 3 http://www.hobbytronics.co.uk/a4988-stepper-motor-driver?keyword=a4988
Motor hook-up wire 18m? Thick enough for 1.5A stock
Motor power hook-up wire 1m? Thick enough for 4.5A
Logic hook-up wire 9x 10cm? I used some ribbon cable stock
Terminal block 12 way So that motor wires can be attached/detached without soldering. stock

Variations

It would be very straightforward to extend this layout for four drivers. If anyone wants the original OpenOffice Draw files (no, really, I used OpenOffice Draw) to do that, let me know.

It ought to be possible to connect one of these to a parallel port and drive it from EMC or other PC CNC software.

Makers

The stripboard stepper driver carrier board has been successfully constructed and used by: