Hex Inverters with Open-Collector Outputs using 74LS05

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Aim

To study and verify the truth table of Hex Inverters with Open-Collector Outputs using 74LS05.

Learning Objectives

1. To understand the behavior and demonstrate the operation of Hex Inverters with Open-Collector Outputs using 74LS05.
2. To apply knowledge of the fundamental gates to create truth tables.
3. To develop digital circuit building and troubleshooting skills.
4. To understand key elements of TTL logic specification or datasheets.

IC Used

For Hex Inverters with Open-Collector Outputs:
IC NumberIC Name
74LS05Hex Inverters with Open-Collector Outputs

Procedure

1. Place the IC on IC Trainer Kit.
2. Connect VCC and ground to respective pins of IC Trainer Kit.
3. Implement the circuit as shown in the circuit diagram.
4. Connect the inputs to the input switches provided in the IC Trainer Kit.
5. Connect the outputs to the switches of O/P LEDs
6. Apply various combinations of inputs according to the truth table and observe the condition of LEDs.
7. Note down the corresponding output readings for various combinations of inputs.
8. Power Off Trainer Kit, disconnect all the wire connections and remove IC's from IC-Base.

Theory

An open collector is a common type of output found on many integrated circuits (IC), which behaves like a switch that is either connected to ground or disconnected.

NOT gate is a digital circuit that has a single input and single output. The output of NOT gate is the logical inversion of input. Hence, the NOT gate is also called an inverter.

Logic NOT Gates are available using digital circuits to produce the desired logical function. The standard NOT gate is given a symbol whose shape is of a triangle pointing to the right with a circle at its end. This circle is known as an "inversion bubble". Logic NOT gates provide the complement of their input signal and are so called because when their input signal is "HIGH" their output state will NOT be "HIGH". Likewise, when their input signal is "LOW" their output state will NOT be "LOW". As they are single-input devices, logic NOT gates are not normally classed as "decision" making devices

Boolean Expression Y = A'

"If A is true, then Y is false"

This NOT gate produces an output Y, which is the complement of input, A.

Precautions

1. Make the connections according to the IC pin diagram.
2. The connections should be tight on trainer kit.
3. The Vcc and ground should be applied carefully at the specified pin only.

Conclusion

We have learned the Hex Inverters with Open-Collector Outputs using 74LS05 IC according to the IC pin diagram.