2004 Dec 22

9

Philips Semiconductors

Product specification

Universal LCD driver for low

multiplex rates

PCF8576D

6

FUNCTIONAL DESCRIPTION

The PCF8576D is a versatile peripheral device designed

to interface any microprocessor/microcontroller with a

wide variety of LCDs. It can directly drive any static or

multiplexed LCD containing up to four backplanes and up

to 40 segments.

The display configurations possible with the PCF8576D

depend on the number of active backplane outputs

required. A selection of display configurations is shown in

Table 1; all of these configurations can be implemented in

the typical system shown in Fig.5.

The host microprocessor/microcontroller maintains the

PCF8576D. The internal oscillator is enabled by

voltages for the multiplexed LCD waveforms are

generated internally. The only other connections required

application.

Table 1

Selection of display configurations

NUMBER OF

7-SEGMENTS NUMERIC

14-SEGMENTS

ALPHANUMERIC

DOT MATRIX

BACKPLANES

SEGMENTS

DIGITS

INDICATOR

SYMBOLS

CHARACTERS

INDICATOR

SYMBOLS

4

160

20

20

10

20

160 dots (4

× 40)

3

120

15

15

8

8

120 dots (3

× 40)

2

80

10

10

5

10

80 dots (2

× 40)

1

40

5

5

2

12

40 dots (1

× 40)

HOST

MICRO-

PROCESSOR/

MICRO-

CONTROLLER

SDA

SCL

OSC

40 segment drives

4 backplanes

LCD PANEL

(up to 160

elements)

PCF8576DU

A0

8

7

2, 3

1, 58, 59

613

9

101112

A1

A2

SA0

mdb079

R

≤

Fig.5 Typical system configuration.

The resistance of the power supply lines must be kept to a minimum.

For chip-on-glass applications, due to Indium Tin Oxide (ITO) track resistance, each supply line must be routed separately

between the chip and the connector.