DMController only build page

Created by: Lester Caine, Last modification: 9 December 2012

While the main driver board contains all the components to provide a 2Amp 24V stepper driver there are situations where a higher power driver would be useful, and assembling a controller only version of the board is required. This is used in the DMSuper and is now available as an optional kit. Power for the controller can be taken from the driver power supply where that is below 60V, but is best supplied by a separate 5V supply above that voltage, in which case the on board switching power supply can be omitted. The higher voltage regulator allows the DMSuper power supply to be used directly into the regulator.

DM-Controller Only Cut down parts list. Includes parts for mounting to a front panel.
Using a diecast or plastic box for a housing leaves a problem with getting the countersunk screws tight to the surface, as the chamfer goes right through the surface of the box. Using an M4 washer ensures that the screws can be tightened without a problem.

The switch board assembly is identical to the main construction guide.

DM Controller only - Wire links
The green link is only required if the power supply is also being used.

DM Controller only - Resistors
Only eight resistors are required for this build.

DM Controller only - Small parts
The crystal and it's capacitors along with the output driver. The diodes near the power supply can be omitted if the board is to be powered from 5V directly.

DM Controller only - Sockets
The two IC's are fitted in sockets for convenience, and the contrast potentiometer is about the same hight components wise.

DM Controller only - Headers
Box headers for the output cable and the connection to the switch board.

DM Controller only - Capacitors
Only the capacitor adjacent to the PIC needs to be fitted if the boarc is powered from a 5V feed. The

DM Controller only - Display links
The original inter PB ribbon cable is no longer available, and the replacement is less than ideal. The original one could be fitted with a molex header if required to allow making the board unplugable from the display, but the smaler profile of the currently available option is impossible to crimp to. It may be more practical to simply fit a set of wires and crimp molex shells to go to headers on the display.

The large display comes in a number of formats, but all can be modified on their links to provide the 5V needed to power the backlight, so no additional resistor or link is required. These are needed with the smaller display.

DM Controller only - Stepper Cable
The pink enable wire is probably not necessary. As the stepper difers alltend to need a 'disable' to switch them off, the driver is active when there is no power on the unit anyway. With the enable line fitted, the stepper driver is only powered when the LED on the controller is lit, but is free otherwise. Leaving out the connection ensures that the motor is always driven and with most drivers will drop back uo 50% current when there is no step pulse for a period of time.

What we still need to sort out is the power wiring arrangement for the various options. 5V could be provided directly to the 9 Way D connector, or the fan connector could be utilised to provide a power jack connection for 5V. The high voltage supply is wired to the PL1 and 2 pins on the board, although simply wiring off the back of the board is easier.