I mentioned that I will be making a new board to drive my matrix display and I have. This here is a DC-DC power supply for the new matrix driver. What makes this interesting is the method I used to turn on the power. I have plans to encase everything (RGB matrix + driver board + power supply board) up once it’s completed. There will be no external switches whatsoever. So, how does one switch on the power without any accessible switch? My answer is to use two regular rolling-ball tilt switches.
ZIF stands for Zero Insertion Force. Check out the wiki entry here. ZIF sockets are commonly used to program microcontrollers or to test ICs. Most are familiar with ZIF sockets for DIP ICs. I’ve always found those to be rather redundant, breadboards worked just fine for me.
Since I started using more surface mount ICs, I tend to buy extras and also a bunch of breakout boards to go with it. That’s because I like to test out whatever new ICs I just bought. There’s no way to do that unless I solder the ICs onto at least a breakout board with header pins so that it’s breadboard friendly.
Well, not anymore. I’ve just bought myself 2 ZIF sockets for small outline ICs (SOIC) from eBay. Some manufacturers call it small outline package (SOP or even just SO) although, that shoud technically be referring to a smaller family of ICs (like SSOP or TSOP). Should have gotten these a long time ago. Would’ve saved me a lot of money and trouble.
Ok, up until now, I haven’t been using my blog for it’s intended purpose, which is as a project log. What I had been doing was basically using it as a showcase for my completed projects. So, for the very first time, I’ll post on something that’s yet to be completed (and possibly never will).
I’ve mentioned giving my brother my old PICkit 2 clone. He was embarking on a project involving LED matrix displays. I’ve never used these before so I tought it might be fun to play with one. So I got myself the beefiest of LED matrix displays, an RGB 8×8. That’s a total of 192 individual LEDs.
Completed this a while ago, but was too lazy to write a post. Anyways, here it is, my new and (aesthetically) improved PICkit 2 clone. As I’ve mention in this post, I didn’t come up with the circuit but got it from MCU Hobby.
What I did was redo the layout. Everything is surface mounted, even the header that’s not supposed to be.
First, let’s look at how my old PICkit 2 clone looked like:
In case the title of this post didn’t give it away, this is a board that takes a low supply voltage, boost it up, and then regulate it back down to the correct voltage. In this case, 3.3V.
This board is meant to power an RGB LED matrix display that I’m working on. The input voltage will be coming from a pair of AA batteries.
I’ve recently been moving towards prototyping with surface mount components. Kinsten brand presensitized PCBs was my first choice. I did a lot of trials but the results were never really satisfactory. Maybe I was just being too particular. The PCBs that turned out should be functional, except they weren’t aesthetically pleasing.
So, after nearly exhausting my stock of presensitized boards, I decided it was time to turn to BatchPCB. From submitting my designs to receiving my PCBs was rather quick really, only about 3 weeks. I guess I got lucky. Check out some pictures I took of the PCBs after the break.
I have been using 0.8mm tungsten carbide drill bits for quite a while. I use it with a rotary tool free-handed, no drill press. I read all around the internet that these bits are really brittle and should not be used without a press. Well, I have never broken a single bit.
Lately, I’ve been wanting to get some smaller bits. I have about 10 pieces of 0.8mm bits from Ebay. Since I had such success with these bits, having 10 of them was rather redundant and wasteful. So, I thought I should get assorted sizes this time around, which means only 1 piece of each size. At these smaller sizes, I’m not really that confident with my hands.
Thinking about it, I noticed I had a pair of ball bearing drawer slides lying around. Aha, with some MDF scraps, a couple of hose clamps, and some screws, I could whip up a homemade drill press.