3 comments After I wrote the stress test article, I decided to put a voltmeter across the drain and source of the MOSFET and figure out what the voltage drop was. I hooked up the output to an LED ornament, watched the brightness cycle up and down, and put my probes on the MOSFET. What I expected […]
0 comments One of the points of the expander is to be able to drive bigger loads than the 18mA that the WS2811 gives you directly. Much bigger loads. To do that, I needed something that would stress the system, and I needed to verify that the design worked with 12V. First off, I needed to cut […]
0 comments After a bit of waiting, the boards showed up from OSHPark. they looked fine as far as I could tell. I had all the other parts to do a board, but I needed a paste stencil. I went into pcbnew, chose File->Export, and then chose to export the F.Mask (ie solder mask) layer to a […]
0 comments More revisions. I posted the design to /r/PrintedCircuitBoard, and of the comments said: “Do you need pullups on the outputs of WS2811?” And of course, I was confident the answer was “no”. For about 5 seconds. And then I measured the WS2811 I have in my breadboard; it gave a nice solid sink when it […]
1 comment I’ve done quite a few improvements on the board. Let’s look at before and after: My usual flow is to do some changes, and then load the board into OSHPark and see how it previews. And then make changes. I’ve probably redone the majority of the traces on the board. The big changes are: I […]
3 comments I’m starting a new decorations project that will involve a fair number of standard LEDs, but not addressable ones. I have a few different use scenarios: Plug into a standard USB power supply. Power directly with 120 VAC. Power either with 5V or 12V and have an easily way to control brightness… The first two […]
5 comments I’ve been working on a project that I think is one of my stupider ones, and it’s time to share it so that I can move onto something that is slightly less stupid. I build a little board that I sell on Tindie that allows you to use the WS2812 addressable LED protocol to drive […]
1 comment I’m not known for the cleanliness of my workspaces; my office desk is a mess right now, my garage workbench is a mess, as are my other workbenches. But my electronics one is messy enough to be problematic, and the root problem is that there’s just too much stuff one the workbench; power supply, oscilloscope, […]
0 comments Having chosen MOSFETs, I went off to do some board design. I’m hoping this will be a very simple design; it needs to provide power to the ESP, connect ESP outputs to the driving MOSFETs, and provide connections for the loads to the MOSFETs. Here’s the schematic: On the right we have all of the […]
0 comments I’m working on a new display for the upcoming holiday season – actually a couple of them – and I need some new controller hardware to drive them. Here are the basic requirements that I jotted down: 8 outputs (perhaps expandable to 16) Each output can drive 1 amp at 12V Designed to deal with […]