PSMD Triple Axis Stepper Driver
PSMD Triple Axis Driver - a carrier board for three Pololu stepper driver boards. This is originally intended to be used to replace three MakerBot Stepper Motor Drivers on whichever type of bot they may be on.
This board is partially based on Adrian's Pololu_Electronics and the MakerBot Generation 3 Electronics (Gen3) and Generation 4 Electronics (Gen4) Stepper Motor Drivers. It has the same 10-pin interface as a Gen3 Stepper Driver but can easily be used with Gen4 electronics as well. There are Gen4-style endstop connectors to provide updated mechanical endstop connections for Gen3 motherboards.
This board has been designed to prevent problems with overheating while still taking as little of space as possible. In order to lower overheating issues the space below the drivers themselves has been left open, and the ends of the airflow channel is not obstructed so that air can flow naturally. If it is mounted in an area with very little airflow a small fan can me mounted (with pull-ties or twist-ties) to two holes in the PCB to blow air directly over the drivers. There is a screw terminal that provides 12V. (However, this board has been tested on all types of bots, including the enclosed space of a Thing-O-Matic, all without heat-sinks on the drivers, and not once has this fan been needed.)
There is also a jumper that, when removed, disconnects the 12V from the PSU power connector and allows you to provide up to 35V in through the screw terminal. Note: The drivers can handle voltage up to 35V, but the resistors on the LEDs and the capacitors on the back are chosen based on 12V, so these components might blow out. The LEDs are not required, but you could piggyback 1206-size resistors onto the ones already there in order to protect the LEDs without having to replace the resistors. The capacitors are only rated for 25V and should be replaced for anything over 20V, since they are required.
Set the microstepping levels by flipping the DIP switches on the back of the board. There is a legend on the back of the PCB explaining the settings. The options are Full-stepping, 1/2, 1/4, 1/8th , and 1/16th microstepping.
Insert the Pololu drivers into their sockets. You only need the drivers you will use -- you can leave positions empty. It is important that you get the drivers into the correct positions in the headers, however. I recommend placing them in from top-to-bottom or bottom-to-top, making sure that all header positions are filled with pins and none are hanging off.
All files are available for download on the Thingiverse page.
They are also being manufactured and will be available for purchase soon fully assembled.