A complex programmable logic device (CPLD), is a complex device than programmable logic devices discussed in previous sections. CPLD contains the circuitry similar to PAL devices. Figure below shows the typical CPLD architecture having four function blocks of PLDs.
The function blocks has programmable interconnections. A switch matrix is used for function blocks to function blocks interconnections. Further, switch matrix in a CPLD may or may not be fully connected. This shows that, some of the connections between function block outputs and inputs are not supported in the CPLD. The complexity of a typical PAL device is around few hundred logic gates whereas the complexity of CPLD is around tens of thousands of logic gates. The CPLDs has predictable timing characteristics hence are suitable for critical control applications and other applications where a high performance level is required. Further, due to low power consumption and low cost, CPLDs are mostly used for battery-operated portable applications such as mobile phones, digital assistants etc.
Complex Programmable Logic Device Question and Answers
Complex Programmable Logic Device Quiz