INTRODUCTION
For me, the first examination at the university for this year will be “Logic Networks”. My electronics-deviance how could resist to implement a logic gate family from scratch? Here it is, Diode Transistor Logic the flint-stones way! DiTieL let’s go!!!
I’ve decided to use only commonly available components:
- 2N2222 NPN
- 1N4148 diodes
- 1kOhm resistors
- 10kOhm resistors
UNIVERSAL GATES
NOT, AND, OR combined together could make any kind of combinatorial logic circuits as example I’ve tried to make an EX-OR.
This basic implementation works but have soma major drawback specifically on the port couplings, output driving stages.
I’ve soon found that the use of a complementary type NPN and PNP transistor solves this problems.
Part list changed:
- BC547 NPN
- BC557 PNP
- 1N4148 diodes
- 1kOhm resistors
- 10kOhm resistors
Measures confirm that this implementation is better than single 2N2222 version as per power efficency
