An OR gate is a logic gate the place the output goes HIGH (or “1”) if any of its inputs are HIGH. So if A OR B is HIGH, the output Q additionally turns into HIGH.
The logic or Boolean expression for an OR gate is which implies:
If A or B is true, then Q is true
OR gates can have greater than two inputs. However irrespective of what number of inputs it has, it’s going to at all times give out a HIGH or logic “1” if certainly one of its inputs is HIGH.
2-input OR Gate Reality Desk
|Enter A||Enter B||Output Q|
3-input OR Gate Reality Desk
|Enter A||Enter B||Enter C||Output Q|
IC Options with OR Gates
- 4071: 4 2-input OR gates
- 4075: Three 3-input OR gates
- 74HC32: 4 2-input OR gates (HC is the household, may also be LS/HCT/…)
- 74HC4075: Three 3-input OR gates (HC is the household, may also be LS/HCT/…)
These ought to all be out there as hobbyist-friendly through-hole chips. Simply be sure to purchase the DIP bundle model.
Instance Circuit: Testing an OR gate
Beneath is an easy sensible circuit you possibly can construct to check how this gate works. A Gentle-Emitting Diode (LED) activates whenever you press both of the buttons A OR B. The circuit demonstrates the fundamental operation of an OR gate.
Subsequent Step within the Logic Gates Tutorial
Take a look at the opposite articles on this logic gates tutorial: