Polygonhell wrote:The drivers are designed to shed heat from the back side of the device, the intent being that a copper pad is placed on the board itself to act as a small heatsink, I suspect that Rambo is in a better position with this than the pololu daughter boards if for no other reason than there is no airflow under the daughter boards.
SureSteppr daughterboards from Panucatt.com are better, IMHO.
SureStepprs are Pololu-compatible, but mount the chips on the underside so a heatsink on the top side will actually cool the chip. Recent SureSteppers also use a TI driver chip instead of the Allegro 49xx. The TI chips are less sensitive to stray voltage on the motor leads.