What you are expected to learn

At the end of this module, you should be able to:

• Identify and explain the function of the basic logic gates.

• Draw the symbols for the basic logic gates.

• Develop truth tables for the basic logic gates.

How to learn from this module

Going through this module can be both a fun and a meaningful learning experience. All you need to do is make use of your time and resources efficiently. To do this, here are some

tips for you:

1. Take time in reading and understanding each lesson. It is better to be slow but sure than to hurry finishing the module only to find out that you missed the concepts you are supposed to learn.

2. Do not jump from one chapter to another. Usually, the lessons are arranged such that one is built upon another, hence an understanding of the first is essential in comprehending the succeeding lessons.

3. Be honest. When answering the test items, do not turn to the key to correction page unless you are done. Likewise, when performing experiments, record only what you have really observed.

4. Safety first. Perform the experiments with extra precaution. Wear safety gears whenever necessary.

5. Don’t hesitate to ask. If you need to clarify something, approach your teacher or any knowledgeable person.

What to do before (Pretest)

• All digital equipment, whether simple or complex, is constructed of only a few basic circuits. These circuits, referred to as logic elements, perform some logic function on binary data.

• There are two basic types of logic circuits: decision-making and memory. Decision-making logic circuits monitor binary inputs and produce an output based on the status of the inputs and the characteristics of the logic circuit. Memory circuits are used to store binary data.

• An AND gate produces a 1 output when all of its inputs are 1s.

• An AND gate performs the basic operation of multiplication.

• An OR gate produces a 1 output if any of its inputs are 1s.

• An OR gate performs the basic operation of addition.

• A NOT gate performs the function called inversion or complementation.

• A NOT gate coverts the input state to an opposite output state.

• A NAND gate is a combination of an AND gate and an inverter.

• A NAND gate produces 1 output when any of the inputs are 0s.

• A NOR gate is a combination of an OR gate and an inverter.

• A NOR gate produces a 1 output only when both inputs are 0s.

• An exclusive OR (XOR) gate produces a 1 output only if both inputs are different.

• An exclusive NOR (XNOR) gate produces a 1 output only when both inputs are the same.

• A buffer isolates conventional gates from other circuitry.

• A buffer provides a high current for heavy loads or fan-outs.

• A 3-state buffer has a high-impedance third state.

Simulation Activity

Logic gates

Logic Gates 2

Binary & Logic Quiz

Circuit Verse

Self Check