This project of mine is the one that is currently used in my CNC router.
Those THB6064AH chips are really good so once I've done this project and made the configurations I forgot about the board.Tech specs:
- PWM Chopper-Type bipolar Stepping Motor Driver IC
- Selectable phase drive (1/2,1/8,1/10, 1/16, 1/20, 1/32, 1/40, 1/64 step)
- High output withstand voltage: VDSS - 50 V
- High output current: IOUT - 4.5 A (peak)
This project is the fourth iteration of the design and now I use an voltage regulator to power the logic for each one of the THB6064 chips out of three found on the board. This I've done as a protection because in a previous version of the design I burned all of the chips by doing a short on the logic power supply.
I also added some Schmitt triggers coupled with LP filters on the STEP signal and I found the the missing steps are gone.
I added some bigger electrolytic capacitors as tank capacitors for each driver because I use only one power supply to power the motors and everything else. Before adding those capacitors, when I powered OFF the CNC controller I could hear that the motors were moved a bit from position with a loud clang. No longer the case with those capacitors in place.
This board is verified and can be used with no fear.
The board looks like:
And the schematic for only one driver out of three required for a 3 axes CNC:
The attached archive contain the following:
- EAGLE design files
- manufacturing files (GERBER files, GCODE drilling file, GCODE outline milling files, PDF with negative films for UV exposure)
- THB6064AH datasheet (useful when setting the microstepping and the decay through the provided dip switches)
The GCODE outline milling is done in 2 steps so it is easier on the milling bit: first to a depth of 1mm and the second will do milling to a depth of 2mm. Milling bit is diamond shaped with dia 1.2mm.
Pass as usual.
LE: made a mistake and posted a previous version of the project. I've corrected the issue.
LLE: To obtain the logic power I use a board like this one:http://www.aliexpress.com/item/New-DC-DC-LM2596HVS-LM2596HV-Adjustable-Step-Down-Buck-Converter-Power-Module-5-60V-input-1/32641621076.html?spm=2114.0101018.104.22.168MgODj&ws_ab_test=searchweb201556_10,searchweb201602_4_10037_10017_507_10033_10032_401,searchweb201603_2&btsid=8a27cfbf-2ad1-4892-9de2-ea793b3bdbf3
This little power supply board (max input voltage of 60V, the LM2596HVS is the high voltage version) is adjusted so it will output a voltage of about 8V from the main power of 40V (I power the motors NEMA23 3A from a 40V/10A main power supply).
The driver board was mounted on a big aluminium heatsink and the THB6064AH IC's were in direct contact and screwed on this heatsink (some thermal grease was used). There was no need for a fan because they hardly heat when in high usage.