## OR Gate (MA168E)

- Details
- Published: Sunday, 06 March 2016 00:00
- Written by Newton C. Braga

The output of an OR gate is high IF either input, A or B, or both, are in the high logic level. Figure 1 shows the symbol and the equivalent circuits.

Figure 1

**Equation 1 **

**2-Input OR gate **

X = A + B

**Where:**

X is the input logic level

A and B are the output logic levels

**Equation 2 **

**3-Input OR Gate **

X – A + B + C

Where:

X is the input logic level

A, B and C are the output logic levels

**Truth Table**