AN563

AN563 Using PIC16C5X Microcontrollers as LCD Drivers Author: Al Lovrich Microchip Technology Inc. INTRODUCTION This application note describes an LCD controller implementation using a PIC16C55 microcontroller. This technique offers display capabilities for applications that require a small display at a low cost, together with the capabilities of the standard PIC16C55 microcontroller. We start by an overview of LCD devices and their theory of operation followed by software implementation issues of the controller. The source code for controlling a multiplexed LCD display is included in Appendix A. LIQUID CRYSTAL DISPLAYS The Liquid Crystal Display (LCD) is a thin layer of “Liquid Crystal Material” deposited between two plates of glass. The raw LCD is often referred to as “glass”. Electrodes are attached to both sides of the glass. One side is referred to as common or backplane, while the other side is referred to as segment. An LCD is modeled as a capacitor, with one side conn...