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.