GENERAL DESCRIPTION
The PCF8820 is a low power CMOS LCD row/column driver, designed to drive grey-scale/ ECB colour dot matrix graphic displays at a multiplex rate of 1 : 67. In the partial screen mode, only 8 rows are driven at a multiplex rate of 1 : 8.
FEATURES
• Single-chip LCD controller and driver for grey-scale/Electrically Controlled Birefringence (ECB) colour
• 4 grey levels/colours (2-bit) definable from 64 levels
• 67 row and 101 column outputs
• Display data RAM 67 × 101 × 2-bit with linear RAM addressing
• Partial screen mode with reduced current consumption (8 rows at top or bottom of display)
• On-chip:
– Generation of LCD supply voltage (VLCDOUT); external supply also possible
– Configurable voltage multiplier factor of 8, 7, 6, 5, 4, 3 or 2; direct drive also possible
– Selectable linear temperature compensation of VLCDOUT
– Generation of intermediate LCD bias voltages
– Oscillator requires no external components; external clock also possible.
• Temperature read-out
• Fast mode I2C-bus interface (400 kbits/s)
• Frame frequency calibration via software
• Software selectable bias configuration
• Compatible with 4-bit, 8-bit or 16-bit microcontrollers
• Multiplex rates of 1 : 67 or 1 : 8
• Logic supply voltage range from 2.5 to 5.5 V (VDD1 to VSS1)
• High voltage generator supply voltage range from 2.7 to 5.5 V (VDD2 to VSS1 and VDD3 to VSS2)
• Bias voltage generator supply voltage range (VLCDIN to VSS1):
– From 7 to 14.5 V at a multiplex rate of 1 : 67
– From 4.5 to 14.5 V in partial screen mode at a multiplex rate of 1 : 8.
• Low power consumption, suitable for battery operated systems
• Slim chip layout, suitable for chip-on-glass applications
• Software selectable top and bottom row swap for adapting driver to different glass-layouts
• CMOS compatible inputs
• Manufactured in silicon gate CMOS process.
APPLICATIONS
• Mobile telecommunication systems
• Battery powered equipment
• Point of sale terminals
• Instrumentation
• Automotive information systems.