3 Input And Gate Using Transistor. The multiple input or gate is shown below. The base terminal of both the transistors t1 and t2 are connected to input a and b respectively through a 10k ohm resistor for each viz.
The bc547 is used here in common emitter configuration. Pnp and npn bipolar junction transistors. What you need a breadboard a bunch of 5k and 10k resistors and transistors a led you can use any npn type transistor for example 2n3904 bc547 bc548 bc549 etc these are basic circuits so they can be improved with diodes for reverse voltage protection for example or can be simplified xor xnor gates.
For building an and logic gate using a transistor we would be using bjt transistors which can be further classified into two types.
Simulate this circuit schematic created using circuitlab. When input a is held high a small current passes through the base of transistor q22. The multiple input or gate is shown below. A with the bottom transistor on you ll get a potential divider between r3 and r4 of about 1 3 through the base emitter junction of q3 so y1 would be about 5 3 v 1 66.
