One of my main concerns for some time have been to find a free development kit that actually works for Raspberry PI. I intended to develop directly on the PI, but the drawback with that is that I need a 3rd screen + keyboard/mouse and I simply have no room for it as is. The…
Earlier I had a BEMF issue with my smaller motor controller, so I have been reading up on other peoples experience and solutions to design my own. What I came up with is 3 changes on the MC4X15A. Added a 0.33F super capacitor on 3.3V protected by a TVS (on the back) at ca 4V.…
The original current sensor logic will use a shunt between the lower HEXFET and ground (low side current sensing). This is fine for 3-phase, DC or Stepper motors, but it will not enable measuring of current on a single, stand alone Half-Bridge. An alternative way of doing this that fix this issue is to measure…
Finally had the time to assemble a 32 x Servo Hat. Have not written any code for it yet, but always nice to see SWD answering and led’s coming up with a 10mA current on the lab psu – Things look normal. Will get down to wrapping up a servo controller and assembling a…
First actually finished draft. I call it 0.9 because I plan some minor changes before I send it out. Firstly the size did not work out as expected. I ended up using 40mm width due to the MCU and mount holes. I first extended it at bottom to get M2 mounting holes. Later I had…
This Motor Controller is still a bit of work in progress, what is remaining is the communication parts and a review of protection logic. The actual challenge here is size. I am mounting components on both sides to get it small, but as it get smaller the PCB routing get far more advanced. I am…
This picture is a Dual DC-/Stepper- Motor shield for Arduino. It is available on various sources for ca 5.- USD +/-. The Picture is borrowed from one of the shops on AliExpress. The interesting thing about these monster chips is that they are full H-Bridges capable of working up to 40V with a 30A continuous output.…
This little fellow have the same layout as a classic 7805 and is a 35V to 3.3V switched regulator capable of 600mA. The circuit handle 42V, but the capacitors will limit the circuit to 35V I think. I just fancied making this as a bread-/vero-board breakout. The entire circuit is 20×10 mm and occupy less…
I was initially quite happy with the way this cable fitted, particularly as I found a trick on how to solder these. But, this is how it looked after having fiddling with it for a day. I could add a proper micro match connector, but they are a bit expensive. Another solution is to add…
Reviewed the design today and the issue is that the way I am testing easily unleash spikes on several hundreds volt since I disconnect a coil with energy in it. The voltage can be extremely high even if it’s close to no energy in it. Two solutions are suggested (1) avoid disconnecting the motor while…