I’ve got the PCB of the Smoothie-compatible 3D printer controller board!
Front of 3DPCB
Backside of 3DPCB
The size fits RAMPS, PrintrBoard, Sanguinololu, (that is 100 x 60 mm), and consists of almost the same components as Smoothieboard.
I did however change some things:
- 3 IPD060N03L Power MOSFETS, two of them connected to PWM
- 4-channel, 12 bit I2C DAC (MCP4728), for current setting of the stepper drivers
- Two-layer PCB (I know, current and heat transfer may not be as good as four-layer, but we’ll have to wait and see)
- Open Hardware – Well, it already is, but this is designed in KiCAD
That’s almost it. One thing about making PCB’s and doing it in KiCAD which I switched to, over summer, is that the vias you place,(well, mine at least), is a module, just named for GND, for connecting grounds together. This means that the solder mask will not cover the vias, unless you specify it.
I was so exited to get the PCB produced, that I forgot to check possibilities with this.
That’s why the solder mask contains what looks like giant holes all over, as well as the silkscreen!
But anyway; No short circuits (as expected), 3.3V DC/DC converter works like a charm.
Reset / ISP circuit designed by my colleague was implemented. This means pressing the reset short, will do a simple reset, but pressing longer (3 secs), will go into the onboard ISP-mode of LPC1769, which makes us able to upload the DFU bootloader, so the rest of the uploads can be done using SD-card.
Uh, yeah… Had some troubles getting the DAC to work.
Debugging I2C DAC for current control of stepper drivers
But with a lot of help from the guys over at Smoothie IRC, and a bus pirate, I got it fixed!
It was the config, which wasn’t supposed to contains tabs in it. These was removed, and of she went!
All I need to do next is connect it to my PrintrBot, then calibrate, configure, connect, test, calibrate again, test some more, and maybe, I will finally print something!
Schematics and board files will be uploaded to GitHub, whenever I get the chance!