- Logic Gates Definition: Logic gates are defined as basic components in digital circuits that perform logical operations based on input signals.
- OR Gate Applications: OR gates detect the occurrence of one or more events, making them useful in safety systems to trigger actions when parameters exceed safe limits.
- AND Gate Functions: AND gates can act as Enable gates to allow data passage or Inhibit gates to block data, useful in frequency measurement.
- Parity Generation: Ex-OR and Ex-NOR gates are used in parity generation and checking, crucial for error detection in data.
- Inverter Uses: NOT gates, or inverters, are used to create square wave oscillators for generating clock signals due to their low power consumption and easy interfacing.
We’ve previously discussed the design, properties, and operation of digital logic gates. This article focuses on their applications. The applications of logic gates are determined by their truth table, which show how they operate. We’ll explore the uses of basic and other common logic gates.
Application of OR gate
OR gates are used when we need to detect one or more events or take action after an event occurs. For example, in an industrial plant, OR gates can trigger safety measures if temperature or pressure exceeds safe levels.
In an industrial plant, if temperature or pressure exceeds safe values, OR gate trigger protective measures. The following diagram shows this setup.
The above figure is a typical schematic diagram where an OR gate is used to detect exceed of temperature or pressure and produce command signal for the system to take required actions.
Application of AND Gate
AND gates can function as Enable gates or Inhibit gate. Enable gates allow data through a channel, while Inhibit gates block it. For example, in frequency measurement, a known gating pulse enables the passage of the waveform to be measured. The diagram below shows this arrangement.
Application of Ex-OR/Ex-NOR Gate
Ex-OR and Ex-NOR gates are used in parity generation and checking. The diagrams below show even and odd parity generator circuits for four data bits.
With the help of these gates parity check operation can be also performed. The diagrams below show even and odd parity check.
Figure (a) shows the parity check using Ex-OR gates and the figure (b) shows the parity check using Ex-NOR gates.
Application of NOT gate or Inverters
NOT gates are also known as inverter because they invert the output given to them and show the reverse result. Now the CMOS inverters are commonly used to build square wave oscillators which are used for generating clock signals. The advantage of using these is they consume low power and their interfacing is very easy compared to other logic gates.
The above figure shows the most fundamental circuit made of ring configuration to generate square wave oscillator. The frequency of this type generator is given by
Where, n represents the number of inverters and tp shows the propagation delay per gate.
