MOSFET breakout

thingiverse

This is a smalll breakout board featuring two logic-level MOSFETS for driving any sorts of heaters, DC motors, solenoids etc. It has been successfully tested as a spindle driver with 32 KHz PWM and a 27 V power supply. I haven't seen any problems with noise / signal stability (tested with an Arduino duemilanove). The MOSFETS are placed on screw terminals to simplify replacement operations just in case some experimental manipulation happens to release the magic smoke. Please note that the schematics and pcb drawing files are in gEDA (not Eagle) format. Instructions This small board can be either printed for toner transfer, milled, or drawn with etch-resist. I milled it. I used this toolpath: gEDA -> gerber and excellon files -> pcb2gcode (the settings are in the millproject file) -> some hand editing -> EMC2/Axis -> CNC engraver / router with 60 degrees 0.2 mm flat end engraving tip and the following drill sizes: 0.9 mm, 1.2 mm (use 1.5 mm rather) and 3 mm. Final cutout was done with a 1.5 mm straight cutter. The MOSFETS received a couple of handcut heatsinks held with thermal pads and a couple of M3 bolts. Depending on your loads (DC motors, Solenoids...) and PWM cycle, you may need a couple of additional smoothing capacitors across the motor's terminals. Make sure to check them for excessive heating! If using electrolytic capacitors double check polarity. Connect the two signal and the ground (middle) terminals to your Arduino or any other PWM source.