PCF8566
NXP Semiconductors
Universal LCD driver for low multiplex rates
Table 3.
Pin description …continued
Symbol
BP0
Pin
13
Description
LCD backplane outputs
BP2
14
BP1
15
BP3
16
S0 to S23
17 to 40
LCD segment outputs
[1] The substrate (rear side of the die) is wired to VDD but should not be electrically connected.
7. Functional description
The PCF8566 is a versatile peripheral device designed to interface any
microprocessor or microcontroller to a wide variety of LCDs. It can directly drive any static
or multiplexed LCD containing up to 4 backplanes and up to 24 segments.
The display configurations possible with the PCF8566 depend on the number of active
backplane outputs required. Display configuration selection is shown in Table 4. All of the
display configurations given in Table 4 can be implemented in the typical system shown in
Figure 4.
The host microprocessor or microcontroller maintains the 2-line I2C-bus communication
channel with the PCF8566.
Biasing voltages for the multiplexed LCD waveforms are generated internally, removing
the need for an external bias generator. The internal oscillator is selected by connecting
pin OSC to VSS. The only other connections required to complete the system are the
power supplies (pins VDD, VSS and VLCD) and the LCD panel selected for the application.
Table 4.
Display configurations
7-segment numeric
Backplanes Elements
14-segment numeric
Dot matrix
Digits
Indicator
symbols
Characters Indicator
symbols
4
3
2
1
96
72
48
24
12
9
12
9
6
4
3
1
12
16
6
96 (4 × 24)
72 (3 × 24)
48 (2 × 24)
24
6
6
3
3
10
PCF8566_7
© NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 — 25 February 2009
6 of 48
NXP [ NXP ]
