What is the difference between CPLD and FPGA?

What is the difference between CPLD and FPGA?

The main difference between CPLD and FPGA is that FPGA PCIe board provides more logical resource and storage element than CPLD. An electronic circuit is a structure consisting of electronic components such as resistors, transistors, etc. Wires or dashes help to connect all these components. An electrical current passes through the components of an electrical circuit. Two technologies we can use to build electronic circuits are CPLD and FPGA.

What is CPLD?

CPLD stands for ​​Complex Programmable Logic Devices. An integrated circuit helps to implement digital systems. CPLD consists of a set of programmable function blocks. There are macro cells in each block. Macro cells are the main building blocks of the CPLD. Function block inputs and outputs are connected via Global Interconnection Matrix. This interconnect matrix is ​​reconfigurable. Therefore, it is not possible to change the contacts between the function blocks. These function blocks are similar to an array of logic gates. It is very crucial to consider programming technology, functional blocking capabilities, and IP capability before designing a CPLD module.

What is FPGA?

FPGA stands for Field Programmable Port Array. It is a semiconductor device. It consists of an array of configurable logic blocks connected using programmable interconnects. It is possible to reprogram an FPGA as per requirements after manufacturing. There are about 330,000 logic blocks with 1100 inputs and outputs on modern FPGA modules. Overall, FPGA modules are non-volatile and easy to use. In addition, they are economical.

Users can design the circuit using the hardware description language and configure that circuit to run a simple gate such as an AND gate or a complex system such as a multi-core processor. It stores all settings in RAM. Therefore, a power failure can erase these settings. The main components of the FPGA are as follows –

  • Programmable Logic Blocks – Allows you to implement logic functions.
  • Programmable Routing (interconnects) – Allows you to implement functions.
  • IO Blocks – It is used to make chip connections.

Difference between CPLD and FPGA Definition

CPLD is an integrated circuit that helps implement digital systems, while FPGA is an integrated circuit configured by a customer or designer after manufacturing.

Logical resources

Logical features are also a big difference between CPLD and FPGA. CPLD provides minimal logical resources, while FPGA provides a huge amount of logical resources and storage elements to create complex systems.

Cost and memory

CPLD modules are economical, but FPGA modules are more expensive than CPLD. In addition, CPLD modules are made up of larger blocks, while FPGA modules are made up of smaller logical blocks. The memory capacity is another major aspect between CPLD and FPGA module. CPLD module uses non-volatile memory. On the other hand, FPGA module uses RAM memory.

Energy consumption                                                     

Furthermore, it is easier to predict delays in the CPLD than in the FPGA. On the other hand, we cannot ignore the aspect of power between FPGA and CPLD. CPLD consumes little power while FPGA consumes more power.


Security is another difference between CPLD and FPGA. Finally, CPLD is suitable for small and medium scale applications, while FPGA is suitable for moderate to complex applications.