Wednesday, 29 February 2012

Programmable logic Devices

 PLD is a pre fabricated IC, which can be customized to implement Boolean functions.
Generally two level logic circuits can be implemented using PLD
Advantages of PLDs are
  1. Shorter design time
  2. Useful for prototyping
PLD consists of AND array which represent product terms, whose output are connected to OR array which represent sum terms and some output circuitry. In most of the PLDs outputs are registered or fed back to input or complemented/ un-complemented outputs, Buffered outputs. Below figure shows the PLD block diagram.

 
There are three types of PLDs based on programmability options of arrays
  • PROM- Programmable read only memory
  • PLA- Programmable logic array
  • PAL- Programmable array logic
Back                                          Contents                                               Next 

No comments:

Post a Comment