transformerless joule thief circuits

This a circuit very similar to a Joule Thief, except that it is using 2 transistors, no transformer core, and only one inductor. Joule Thief based on transformer page is here: http://aranna.altervista.org/dragonsnest/research/joule-thief-led-torch-project-instructions/ I have built these two circuits today and have combined them into one- first stage is the LED torch

working at 32×24 LED matrix, PIC 16f59

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Working at my LED matrix. 768 LEDs! 32×24 pixels. I want to write a 3D graphics demo. There are electrical issues. The display drive did not work correctly and during 3 days I was not able to figure out what’s wrong. So I removed all of the ICs + replaced with more advanced technology. I use a 16f59 microcontroller now … Continue reading

serial LED 7-segment display

I have been working on these for a while now, including to build various prototypes. At one time I used buffer registers to drive the multiplexed LED display, and this works, but it is still quite an effort to wire. I made PCBs based on this technology. The buffer chips still take up considerable PCB space. Then I tested a … Continue reading

new LED matrix, 68k single board computer

I started off with a new prototype, 68008 single board computer, which has PIC bootloader (18f4450), and 128k static RAM. 68008 is a 68k CPU variant which only has 8-bit data bus. It is nearly complete except a few address bus wires. WIKI: http://hitechworld.org/index.php?title=68008_PiKey But I wanted to relax a little there is no need for a race… So I … Continue reading