Of
Diodes
A new series of instructables that will be using tons and tons of diodes. No IC's are aloud, the only semi conductors are diodes and transistors. The only passive components aloud are capacitors, resistors, switches, inductors, and potentiometers (variable resistors for those who don't know). Another rule is it must have more diodes then any other component. I made this all up, and I made up this group to see how creative people can be with electronics without resorting to IC's. My next one (this one is just a little wimpy intro) might use up to 2000 diodes.
This is an intro to Diode Matrix Roms, basically it takes a signal in (switch) and gives an output (number on the display)
NOTE: I couldn't complete a project designed by myself because my breadboard is way too small, but That'll be fixed in later instructables.
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Signing UpStep 1: Parts
1x 7-segment display
1x 10dip switch (I could only find an 8, just less characters to display)
23x signal diodes (cheapest you can find), I had 23, but I could only fit 9 on my board
1x breadboard, preferably big (unlike mine)
Some jumper wire
some sort of power supply, like 2AA or AAA's
wire cutters help











































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This is just what I need for my project. At first I thought about capacitors, but deemed it way too complicated. Also, where would I find a tutorial on doing this?
(By the way, I love what you're doing with these instructables, and I hope you keep going. I prefer transistors to diodes, but still awesome).
-Y
I made a 2 bit plus carry adder out of DTL a few months ago, but I can't find any pictures of it. There were about 15 transistors and 28 diodes.
I'm making a 2 digit adder (xx + xx = xxx) only from diodes
the schematic is a pain in the butt.
Hello
Dr. asked me a question related to the university b Markp ROM on the design of the type of ROM through the Diode Matrix
Q) Design an adoide matrix read only memory that stor the following 20 words:
1-10111101
2-00101011
3-10111100
4-01000011
5-11101000
6-10011001
7-10111011
8-01100111
9-11101001
10-10111101
11-10000110
12-00010111
13-11001100
14-11111000
15-11001101
16-11000001
17-11001111
18-01100110
19-00101011
20-11111111
How to answer it and drawing with diode matrix read only memory??!!
As it stands now, your circuit consumes more power when the LEDs are off than when they are on*. Looking at your schematic, what if you pushed the LEDs to the top (next to the resistors) and then disconnected the cathodes of the LEDs from ground? You could then use your diodes to ground the cathodes of the LEDs. Since the LED + diode is a larger voltage drop, you'll probably have to reduce the size of the resistors to keep the same LED brightness.
It's fun to work with the basic components, isn't it? =D
*Your diodes turn the LEDs off because they have a smaller voltage drop (~0.7v) than the LEDs (~1.3v), right? This creates a larger voltage drop across the resistor when the LED is off, which leads to a larger current, and therefore higher power consumption.
-Y
You should add schematics into the instructable too.
=o)