This show a classic HEXFET half-bridge driver. IR2103 takes 3.3V logic in form of PWM and convert it into levels that can drive the HEXFET’s. This is called a Gate Driver. It’s purpose is to deliver signals on correct voltage levels to drive the HEXFET’s. A typical minimum for a gate driver is 10ich Volt. The…
This is a 1.27 pitch cable soldered directly to my PWM driver. It was easier to do than I first feared with a few tricks. But, I am a bit concerned that my soldering skills are far above average for a hobbyist. This takes a bit of training to get right. I have this issue…
This is just a concept sketch of the driver step for a 4 phase driver. We add the 4th phase, but I only use one current shunt on this. The width is ca 33 mm using the same trick in mounting a 4 pole 5.08 pitch connector on the back. I need to adjust this…
RAMPS are great for driving stepper motors for 3D printers because they are small and cost around 1.- GBP each. They are quite capable of controlling steppers up to 2A with some heat sinks, but controlling steppers above that is a challenge. Available controllers are large and tend to be expensive. Looking at the 3-phase…
The illustration above shows ruffly how servo logic will come out if you bit bang directly. Some of the Arduino libraries does this. As each servo uses up to 50ms on a pulse you can in theory service 20 servos in a second. The limitation here is that you bit-bang one channel at the time…
I had to clean my subscription pages due to the amount of bot’s that joined. Once a bot subscribe they also start commenting every article with nonsense. So for now you need to contact the site on subscribe@basicpi.org and you will be added manually. Add Your name and a valid email address. I apologize for…
I have a Prusa i3 3D printer that I purchased from Hong Kong a few years ago. It was a DIY kit costing around 280.- USD at the time. The printer was good value, but I ran into several problems with it’s control system. The one I use is based on Arduino, but with re-designed electronics…
DRV8301 is a pre-amplifier for 3-phase motor controllers. It is programmable through SPI, handle 60V, contains a 1,5A buck converter and support for 2 current sensors. DRV8302, DRV8303 and DRV8305 are other variants of this. I really want to dig into DRV8305, but they are a bit hard to get and I had my eyes…
This is 2-axis (below) and 3-axis stepper controller for the 28BYJ-48 5-wire stepper motors. The 2-axis version is 55 x 15mm, while the 3-axis one is 50 x 30 mm. They both contain the same electronics (except for connectors), but the 3-axis one is single side assembly. Both uses STM32F103Cx.
Finally done. This picture illustrate the 3 different grounds and the space between the areas that is part of the galvanic isolation. Finally got everything on and routed, so will double check tomorrow (or later today) and order PCB’s. Hopefully this is my x-mas fun project, but I don’t really expect to see the PCB’s…