Philips PCF8576CU-5-F1, PCF8576CU-7-F1, PCF8576CU-F1, PCF8576CU-10-F1, PCF8576CU-12-F1 Datasheet
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INTEGRATED CIRCUITS
DATA SHEET
PCF8576C
Universal LCD driver for low multiplex rates
Product specification |
1998 Jul 30 |
Supersedes data of 1997 Nov 14
File under Integrated Circuits, IC12
Philips Semiconductors Product specification
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Universal LCD driver for low multiplex |
PCF8576C |
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CONTENTS |
8 |
LIMITING VALUES |
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1 |
FEATURES |
9 |
HANDLING |
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DC CHARACTERISTICS |
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GENERAL DESCRIPTION |
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AC CHARACTERISTICS |
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ORDERING INFORMATION |
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11.1 |
Typical supply current characteristics |
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BLOCK DIAGRAM |
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11.2 |
Typical characteristics of LC D outputs |
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PINNING |
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APPLICATION INFORMATION |
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FUNCTIONAL DESCRIPTION |
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12.1 |
Chip-on-glass cascadability in single plane |
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6.1Power-on reset
6.2LCD bias generator
6.3LCD voltage selector
6.4LCD drive mode waveforms
6.4.1Static drive mode
6.4.21 : 2 multiplex drive mode
6.4.31 : 3 multiplex drive mode
6.4.41 : 4 multiplex drive mode
6.5Oscillator
6.5.1Internal clock
6.5.2External clock
6.6Timing
6.7Display latch
6.8Shift register
6.9Segment outputs
6.10Backplane outputs
6.11Display RAM
6.12Data pointer
6.13Subaddress counter
6.14Output bank selector
6.15Input bank selector
6.16Blinker
13BONDING PAD LOCATIONS
14PACKAGE OUTLINES
15SOLDERING
15.1Introduction
15.2Reflow soldering
15.3Wave soldering
15.3.1LQFP
15.3.2VSO
15.3.3Method (LQFP and VSO)
15.4Repairing soldered joints
16DEFINITIONS
17LIFE SUPPORT APPLICATIONS
18PURCHASE OF PHILIPS I2C COMPONENTS
7 |
CHARACTERISTICS OF THE I2C-BUS |
7.1Bit transfer (see Fig.12)
7.2Start and stop conditions (see Fig.13)
7.3System configuration (see Fig.14)
7.4Acknowledge (see Fig.15)
7.5PCF8576C I2C-bus controller
7.6Input filters
7.7I2C-bus protocol
7.8Command decoder
7.9Display controller
7.10Cascaded operation
1998 Jul 30 |
2 |
Philips Semiconductors |
Product specification |
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Universal LCD driver for low multiplex
PCF8576C
rates
1 FEATURES
∙Single-chip LCD controller/driver
∙Selectable backplane drive configuration: static or 2/3/4 backplane multiplexing
∙Selectable display bias configuration: static, 1/2 or 1/3
∙Internal LCD bias generation with voltage-follower buffers
∙40 segment drives: up to twenty 8-segment numeric characters; up to ten 15-segment alphanumeric characters; or any graphics of up to 160 elements
∙40 × 4-bit RAM for display data storage
∙Auto-incremented display data loading across device subaddress boundaries
∙Display memory bank switching in static and duplex drive modes
∙Versatile blinking modes
∙LCD and logic supplies may be separated
∙Wide power supply range: from 2 V for low-threshold LCDs and up to 6 V for guest-host LCDs and high-threshold (automobile) twisted nematic LCDs.
A 9 V version is also available on request.
∙Low power consumption
∙Power-saving mode for extremely low power consumption in battery-operated and telephone applications
∙I2C-bus interface
∙TTL/CMOS compatible
∙Compatible with any 4-bit, 8-bit or 16-bit microprocessors/microcontrollers
∙May be cascaded for large LCD applications (up to 2560 segments possible)
∙Cascadable with 24-segment LCD driver PCF8566
∙Optimized pinning for plane wiring in both and multiple PCF8576C applications
∙Space-saving 56-lead plastic very small outline package (VSO56) or 64-lead low profile quad flat package (LQFP64)
∙No external components
∙Compatible with chip-on-glass technology
∙Manufactured in silicon gate CMOS process.
2 GENERAL DESCRIPTION
The PCF8576C is a peripheral device which interfaces to almost any Liquid Crystal Display (LCD) with low multiplex rates. It generates the drive signals for any static or multiplexed LCD containing up to four backplanes and up to 40 segments and can easily be cascaded for larger LCD applications. The PCF8576C is compatible with most microprocessors/microcontrollers and communicates via a two-line bidirectional I2C-bus. Communication overheads are minimized by a display RAM with auto-incremented addressing, by hardware subaddressing and by display memory switching (static and duplex drive modes).
3 ORDERING INFORMATION
TYPE NUMBER |
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PACKAGE |
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NAME |
DESCRIPTION |
VERSION |
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PCF8576CT |
VSO56 |
plastic very small outline package; 56 leads |
SOT190-1 |
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PCF8576CU |
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chip in tray |
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PCF8576CU/2 |
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chip with bumps in tray |
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PCF8576CU/5 |
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unsawn wafer |
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PCF8576CU/7 |
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chip with bumps on tape |
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PCF8576CU/10 |
FFC |
chip-on-film frame carrier |
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PCF8576CU/12 |
FFC |
chip with bumps on film frame carrier |
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PCF8576CH |
LQFP64 |
plastic low profile quad flat package; 64 leads; body 10 × 10 × 1.4 mm |
SOT314-2 |
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1998 Jul 30 |
3 |
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30 Jul 1998
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4 |
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BLOCK |
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13 |
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17 to 56 |
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DIAGRAM |
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BP0 BP2 BP1 BP3 |
S0 to S39 |
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40 |
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5 |
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BACKPLANE |
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VDD |
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DISPLAY SEGMENT OUTPUTS |
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OUTPUTS |
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LCD |
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DISPLAY LATCH |
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VOLTAGE |
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SELECTOR |
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LCD BIAS |
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SHIFT REGISTER |
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GENERATOR |
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12 |
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VLCD |
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4 |
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PCF8576C |
INPUT |
DISPLAY |
OUTPUT |
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CLK |
TIMING |
BLINKER |
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3 |
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BANK |
RAM |
BANK |
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SYNC |
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SELECTOR |
40 x 4 BITS |
SELECTOR |
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DISPLAY |
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CONTROLLER |
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OSCILLATOR |
POWER- |
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OSC |
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DATA |
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ON |
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POINTER |
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RESET |
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11 |
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COMMAND |
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VSS |
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DECODER |
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2 |
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SUB- |
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SCL |
INPUT |
I2C - BUS |
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ADDRESS |
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1 |
FILTERS |
CONTROLLER |
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COUNTER |
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SDA |
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10 |
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7 |
8 |
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SA0 |
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A0 |
A1 |
A2 |
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MLD332 |
Fig.1 Block diagram;handbook,fullpagewidth |
VSO56. |
multiplex low for driver LCD Universal rates
PCF8576C
Semiconductors Philips
specification Product
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
5 PINNING
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SYMBOL |
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PIN |
DESCRIPTION |
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SOT190 |
SOT314 |
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SDA |
1 |
10 |
I2C-bus serial data input/output |
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SCL |
2 |
11 |
I2C-bus serial clock input |
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3 |
12 |
cascade synchronization input/output |
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SYNC |
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CLK |
4 |
13 |
external clock input |
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VDD |
5 |
14 |
supply voltage |
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OSC |
6 |
15 |
oscillator input |
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A0 to A2 |
7 to 9 |
16 to 18 |
I2C-bus subaddress inputs |
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SA0 |
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19 |
I2C-bus slave address input; bit 0 |
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VSS |
11 |
20 |
logic ground |
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VLCD |
12 |
21 |
LCD supply voltage |
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BP0, BP2, BP1, BP3 |
13 to 16 |
25 to 28 |
LCD backplane outputs |
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S0 to S39 |
17 to 56 |
29 to 32, 34 to 47, 49 to 64, 2 to 7 |
LCD segment outputs |
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n.c. |
− |
1, 8, 9, 22 to 24, 33 and 48 |
not connected |
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1998 Jul 30 |
5 |
Philips Semiconductors |
Product specification |
|
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Universal LCD driver for low multiplex
PCF8576C
rates
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SDA |
1 |
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56 |
S39 |
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SCL |
2 |
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55 |
S38 |
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SYNC |
3 |
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54 |
S37 |
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CLK |
4 |
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53 |
S36 |
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VDD |
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5 |
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52 |
S35 |
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OSC |
6 |
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51 |
S34 |
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A0 |
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S33 |
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A1 |
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49 |
S32 |
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A2 |
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48 |
S31 |
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SA0 |
10 |
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47 |
S30 |
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VSS |
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11 |
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46 |
S29 |
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VLCD |
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12 |
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45 |
S28 |
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BP0 |
13 |
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S27 |
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BP2 |
14 |
PCF8576CT |
43 |
S26 |
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BP1 |
15 |
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42 |
S25 |
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BP3 |
16 |
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41 |
S24 |
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S0 |
17 |
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40 |
S23 |
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S1 |
18 |
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39 |
S22 |
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S2 |
19 |
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38 |
S21 |
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S3 |
20 |
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37 |
S20 |
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S4 |
21 |
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36 |
S19 |
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S5 |
22 |
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35 |
S18 |
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S6 |
23 |
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34 |
S17 |
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S7 |
24 |
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33 |
S16 |
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S8 |
25 |
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32 |
S15 |
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S9 |
26 |
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31 |
S14 |
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S10 |
27 |
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30 |
S13 |
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S11 |
28 |
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S12 |
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MLD334 |
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Fig.2 Pin configuration; VSO56.
1998 Jul 30 |
6 |
Philips Semiconductors |
Product specification |
|
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Universal LCD driver for low multiplex
PCF8576C
rates
handbook, full pagewidth
S33 |
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S32 |
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S31 |
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S30 |
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S29 |
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S28 |
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S27 |
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S26 |
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S25 |
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S24 |
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S23 |
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S22 |
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S21 |
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S20 |
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S19 |
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S18 |
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64 |
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49 |
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n.c. 1 S34 2 S35 3 S36 4 S37 5 S38 6 S39 7
n.c. 8
PCF8576CH
n.c. 9 SDA 10 SCL 11 SYNC 12 CLK 13 VDD 14 OSC 15 A0 16
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A1 |
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A2 |
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SA0 |
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V |
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LCD |
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n.c. |
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n.c. |
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n.c. |
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BP0 |
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BP2 |
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BP1 |
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BP3 |
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S0 |
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S1 |
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S2 |
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S3 |
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SS |
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V |
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48 n.c.
47 S17
46 S16
45 S15
44 S14
43 S13
42 S12
41 S11
40 S10
39 S9
38 S8
37 S7
36 S6
35 S5
34 S4
33 n.c.
MLD333
Fig.3 Pin configuration; LQFP64.
1998 Jul 30 |
7 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
6 FUNCTIONAL DESCRIPTION
The PCF8576C is a versatile peripheral device designed to interface to any microprocessor/microcontroller to 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 PCF8576C depend on the number of active backplane outputs required; a selection of display configurations is given in Table 1.
All of the display configurations given in Table 1 can be implemented in the typical system shown in Fig.4.
The host microprocessor/microcontroller maintains the 2-line I2C-bus communication channel with the PCF8576C. The internal oscillator is selected by tying OSC (pin 6) to VSS (pin 11). The appropriate biasing voltages for the multiplexed LCD waveforms are generated internally. The only other connections required to complete the system are to the power supplies (VDD,
VSS and VLCD) and the LCD panel chosen for the application.
Table 1 Selection of display configurations
NUMBER OF |
7-SEGMENTS NUMERIC |
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14-SEGMENTS |
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ALPHANUMERIC |
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DOT MATRIX |
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BACKPLANES |
SEGMENTS |
DIGITS |
INDICATOR |
CHARACTERS |
INDICATOR |
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SYMBOLS |
SYMBOLS |
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4 |
160 |
20 |
20 |
10 |
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20 |
160 dots (4 × 40) |
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3 |
120 |
15 |
15 |
8 |
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8 |
120 dots (3 × 40) |
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2 |
80 |
10 |
10 |
5 |
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10 |
80 dots (2 × 40) |
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1 |
40 |
5 |
5 |
2 |
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12 |
40 dots (1 × 40) |
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VDD |
R |
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2CB |
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V |
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V |
LCD |
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DD |
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SDA |
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12 |
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HOST |
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1 |
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17 to 56 |
40 segment drives |
LCD PANEL |
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MICRO- |
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SCL |
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PCF8576CT |
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PROCESSOR/ |
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2 |
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(up to 160 |
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MICRO- |
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OSC |
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elements) |
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CONTROLLER |
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13 to 16 |
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VSS |
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Fig.4 Typical system configuration.
1998 Jul 30 |
8 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
6.1Power-on reset
At power-on the PCF8576C resets to a starting condition as follows:
1.All backplane outputs are set to VDD.
2.All segment outputs are set to VDD.
3.The drive mode ‘1 : 4 multiplex with 1¤3bias’ is selected.
4.Blinking is switched off.
5.Input and output bank selectors are reset (as defined in Table 5).
6.The I2C-bus interface is initialized.
7.The data pointer and the subaddress counter are cleared.
Data transfers on the I2C-bus should be avoided for 1 ms following power-on to allow completion of the reset action.
6.2LCD bias generator
The full-scale LCD voltage (Vop) is obtained from
VDD - VLCD. The LCD voltage may be temperature compensated externally through the VLCD supply to pin 12.
Fractional LCD biasing voltages are obtained from an internal voltage divider of the three series resistors connected between VDD and VLCD. The centre resistor can be switched out of the circuit to provide a 1¤2bias voltage level for the 1 : 2 multiplex configuration.
6.3LCD voltage selector
The LCD voltage selector co-ordinates the multiplexing of the LCD in accordance with the selected LCD drive configuration. The operation of the voltage selector is controlled by MODE SET commands from the command decoder. The biasing configurations that apply to the preferred modes of operation, together with the biasing
characteristics as functions of Vop = VDD - VLCD and the resulting discrimination ratios (D), are given in Table 2.
A practical value for Vop is determined by equating Voff(rms) with a defined LCD threshold voltage (Vth), typically when
the LCD exhibits approximately 10% contrast. In the static drive mode a suitable choice is Vop > 3Vth approximately.
Multiplex drive ratios of 1 : 3 and 1 : 4 with 1¤2bias are possible but the discrimination and hence the contrast
ratios are smaller ( 3 = 1.732 for 1 : 3 multiplex or
21
---------- = 1.528 for 1 : 4 multiplex). 3
The advantage of these modes is a reduction of the LCD full-scale voltage Vop as follows:
· |
1 : 3 multiplex (1¤2bias): |
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Vop = |
6 ´ Voff á rmsñ = 2.449 Voff(rms) |
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· |
1 : 4 multiplex (1¤2bias): |
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V |
= |
(4 ´ 3) |
= 2.309 V |
off(rms) |
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op |
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3 |
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These compare with Vop = 3 Voff(rms) when 1¤3bias is used.
Table 2 Preferred LCD drive modes: summary of characteristics
|
NUMBER OF |
LCD BIAS |
Voff(rms) |
Von(rms) |
Von(rms) |
|
LCD DRIVE MODE |
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-------------------- |
-------------------- |
D = -------------------- |
|
BACKPLANES |
LEVELS |
CONFIGURATION |
Vop |
Vop |
Voff(rms) |
static |
1 |
2 |
static |
0 |
1 |
¥ |
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1 : 2 |
2 |
3 |
1¤2 |
0.354 |
0.791 |
2.236 |
1 : 2 |
2 |
4 |
1¤3 |
0.333 |
0.745 |
2.236 |
1 : 3 |
3 |
4 |
1¤3 |
0.333 |
0.638 |
1.915 |
1 : 4 |
4 |
4 |
1¤3 |
0.333 |
0.577 |
1.732 |
1998 Jul 30 |
9 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
6.4LCD drive mode waveforms
6.4.1STATIC DRIVE MODE
The static LCD drive mode is used when a single backplane is provided in the LCD. Backplane and segment drive waveforms for this mode are shown in Fig.5.
V DD
BP0
VLCD
V DD
Sn
VLCD
VDD
S n 
1
VLCD
Tframe
LCD segments
state 1 |
state 2 |
(on) |
(off) |
(a) waveforms at driver
V op
state 1 |
0 |
Vop
V op
state 2 |
0 |
Vop
(b) resultant waveforms |
|
at LCD segment |
MBE539 |
Vstate1(t) = VSn(t) –VBP0(t)
Von(rms) = Vop
Vstate2(t) = VSn + 1(t) –VBP0(t)
Voff(rms) = 0 V
Fig.5 Static drive mode waveforms (Vop = VDD − VLCD).
1998 Jul 30 |
10 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
6.4.21 : 2 MULTIPLEX DRIVE MODE
When two backplanes are provided in the LCD, the 1 : 2 multiplex mode applies. The PCF8576C allows use of 1¤2bias or 1¤3bias in this mode as shown in Figs 6 and 7.
VDD
BP0 (VDD 
VLCD )/2
VLCD
VDD
BP1 (VDD 
VLCD )/2
VLCD
VDD
Sn
VLCD
VDD
S n 
1
VLCD
Vop
Vop /2
state 1 |
0 |
Vop /2
Vop
Vop
Vop /2
state 2 |
0 |
Vop /2
Vop
Vstate1(t) = VSn(t) –VBP0(t)
Von(rms) = 0.791Vop
Vstate2(t) = VSn(t) –VBP1(t)
Voff(rms) = 0.354Vop
Tframe
LCD segments
state 1 state 2
(a) waveforms at driver
(b) resultant waveforms
MBE540
at LCD segment
Fig.6 Waveforms for the 1 : 2 multiplex drive mode with 1¤2bias (Vop = VDD - VLCD).
1998 Jul 30 |
11 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
BP0
BP1
Sn
S n 
1
state 1
state 2
VDD |
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VDD |
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VDD |
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VLCD |
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state 1 |
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VDD |
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state 2 |
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VDD |
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VDD |
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VLCD |
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VDD |
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VDD |
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VDD |
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VLCD |
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VLCD |
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Vop
2Vop /3
Vop /3
0
Vop /3
2Vop /3
Vop
Vop
2Vop /3
Vop /3
0
Vop /3
2Vop /3
Vop
(b) resultant waveforms |
MBE541 |
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at LCD segment |
||
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Vstate1(t) = VSn(t) –VBP0(t)
Von(rms) = 0.745Vop
Vstate2(t) = VSn(t) –VBP1(t)
Voff(rms) = 0.333Vop
Fig.7 Waveforms for the 1 : 2 multiplex drive mode with 1¤3bias (Vop = VDD - VLCD).
1998 Jul 30 |
12 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
6.4.31 : 3 MULTIPLEX DRIVE MODE
When three backplanes are provided in the LCD, the 1 : 3 multiplex drive mode applies, as shown in Fig.8.
|
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Tframe |
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VDD |
LCD segments |
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BP0 |
VDD |
Vop /3 |
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VDD |
2Vop /3 |
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state 1 |
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state 2 |
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BP1 |
VDD |
Vop /3 |
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2Vop /3 |
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BP2/S23 |
VDD |
Vop /3 |
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1 |
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0 |
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state 2 |
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MBE542 |
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at LCD segment |
Vstate1(t) = VSn(t) –VBP0(t)
Von(rms) = 0.638Vop
Vstate2(t) = VSn(t) –VBP1(t)
Voff(rms) = 0.333Vop
Fig.8 Waveforms for the 1 : 3 multiplex drive mode (Vop = VDD − VLCD).
1998 Jul 30 |
13 |
Philips Semiconductors |
Product specification |
|
|
Universal LCD driver for low multiplex
PCF8576C
rates
6.4.41 : 4 MULTIPLEX DRIVE MODE
When four backplanes are provided in the LCD, the 1 : 4 multiplex drive mode applies, as shown in Fig.9.
BP0
BP1
BP2
BP3
Sn
Sn 
1
S n 
2
Sn 
3
state 1
state 2
VDD |
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VDD |
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(a) waveforms at driver |
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Vop |
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(b) resultant waveforms |
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at LCD segment |
LCD segments
state 1 |
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state 2 |
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Vstate1(t) |
= VSn(t) –VBP0(t) |
Von(rms) |
= 0.577Vop |
Vstate2(t) = VSn(t) –VBP1(t)
Voff(rms) = 0.333Vop
MBE543
Fig.9 Waveforms for the 1 : 4 multiplex drive mode (Vop = VDD − VLCD).
1998 Jul 30 |
14 |
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