The World of Programmable Logic Devices
by Yuvi K - December 16, 2023
What are Programmable Logic Devices?
Programmable logic devices (PLDs) are computer chips which are designed to be used at the hardware level in embedded systems and other applications. They are programmable logic functions which enable you to implement complex digital logic designs in a single device. PLDs are used in a variety of applications such as digital signal processing, computer systems, test and measurement equipment, control systems and automotive applications. PLDs are widely used in industry because of their low cost, easy to use interface and scalability.
Types of Programmable Logic Devices
There are several types of programmable logic devices, each offering its own unique advantages and disadvantages.
PLDs
Programmable logic devices (PLDs) come in a variety of forms. The most common type is Field Programmable Gate Arrays (FPGAs) which consist of a single chip that can be programmed to create complex digital circuits. FPGAs are highly customizable, providing the ability to design and implement customized logic in a single device.
CPLDs
Complex Programmable Logic Devices (CPLDs) are similar to FPGAs in terms of their flexibility but provide more features and are more powerful. CPLDs are used in applications requiring more complex logic such as motor control, digital signal processing, embedded systems and DSP applications.
ASICs
Application Specific Integrated Circuits (ASICs) are chips specifically designed for one particular application. Unlike programmable devices, ASICs are designed to perform specific tasks and cannot be further programmed. They are typically used in applications requiring very high performance with low power consumption.
HPLDs
High-performance Programmable Logic Devices (HPLDs) are designed to provide high performance along with very low power consumption. They are used for high-speed applications such as switching, communications and digital signal processing.
Advantages and Disadvantages of Programmable Logic Devices
Programmable logic devices have many advantages such as low cost, ease of use and scalability. However, there are some disadvantages associated with them.
Advantages
- Low cost – PLDs are much less expensive than ASICs, making them ideal for applications where cost is a major factor.
- Ease of use – PLDs are easy to program and configure, providing better control over logic operations.
- Scalability – PLDs are highly scalable, allowing them to be easily upgraded or modified for new applications.
Disadvantages
- Lack of specialized tools – PLDs require specialized tools to program which can increase the overall cost of the system.
- Long design times – PLDs require long design times, making them unsuitable for applications where time is a factor.
- Performance – PLDs may not be able to match the performance of dedicated logic circuits.
Conclusion
Programmable logic devices offer a wide range of advantages for embedded system and other applications. They are highly cost effective, simple to use and can be easily upgraded or modified for new applications. However, they do have some drawbacks such as the need for specialized tools, long design times and lower performance than dedicated logic chips. Nevertheless, PLDs remain a viable option for many applications.
