Circuit Design

When you have an idea or a requirement for an electronic circuit, you need to first design it before you can assemble or fabricate it. There are several software design tools that not only will help you design your circuit but also test it by simulating various inputs and determining the output.

The process of designing a circuit involves understanding the functionality required from the circuit then connecting all the required components in a meaningful sequence and order so that they will work together to provide the desired functionality.

Electronic circuit design requires a clear understanding of all electronic components, how they function individually and how they connect and function interactively with each other, their power requirements, the voltage, and current through each component and the circuit as a whole.

While very basic circuits may be designed using individual components, most complex circuits are designed around ICs (Integrated Circuits). These are pre-designed circuits, performing some of the standard functionality, and they can be reused in circuit designs for custom functionality. ICs in the electronics design field can be considered the equivalent of libraries in the software design field.

Circuits have a logical and physical design.

• In a logical design, the components use their functional specifications, power requirements, and their interconnections to achieve the desired functionality, which is defined. Today, logical design is often done using computer software that uses what is known as a hardware description language (HDL), a specialized computer language used to describe the structure and behavior of electronic circuits. Several software applications, known as electronic design automation (EDA) software, are available for designing electronic circuits. Since modern semiconductor chips can have billions of components, EDA software is essential for their design. The software not only allows the circuits to be designed but also allows their functionality to be simulated on a computer by providing a range of expected inputs and determining the outputs which can be verified against actual requirements. It saves designers' a lot of time in testing and verification, and also errors are caught early before significant time and efforts are invested in physical design.

• In a physical design, the actual physical components are chosen based on size and form (discrete or integrated circuits), connection mechanisms, and power sources depending on where the circuits are needed to use. Sometimes, based on the physical design requirements, there may be a change required to the logical design as well. In case some connections are not possible with the available components. The physical design serves as the input for the actual assembly process of the circuit.