Datasheet

Table Of Contents
2010 Microchip Technology Inc. DS39770C-page 163
PIC18F85J90 FAMILY
16.0 LIQUID CRYSTAL DISPLAY
(LCD) DRIVER MODULE
The Liquid Crystal Display (LCD) driver module
generates the timing control to drive a static or
multiplexed LCD panel. It also provides control of the
LCD pixel data. The module can drive panels of up to
192 pixels (48 segments by 4 commons) in 80-pin
devices, and 132 pixels (33 segments by 4 commons) in
64-pin devices.
The LCD driver module supports these features:
Direct driving of LCD panel
On-chip bias generator with dedicated charge
pump to support a range of fixed and variable bias
options
Up to four commons, with four Multiplexing modes
Up to 48 (80-pin devices) or 33 (64-pin devices)
segments
Three LCD clock sources with selectable prescaler,
with a fourth source available for use with the LCD
charge pump
A simplified block diagram of the module is shown in
Figure 16-1.
FIGURE 16-1: LCD DRIVER MODULE BLOCK DIAGRAM
COM3:COM0
Timing Control
Data Bus
INTRC Oscillator
FOSC/4
T13CKI
192
to
48
MUX
SEG<47:0>
To I/O Pins
24 x 8 (= 4 x 48)
LCD DATA
LCDCON
LCDPS
LCDSEx
LCDDATA0
LCDDATA1
LCDDATA22
LCDDATA23
.
.
.
LCD Bias Generation
LCD Clock
Source Select
LCD
Charge Pump
48
4
Bias
Voltage
8
INTOSC Oscillator