PCF8566_7 © NXP B.V. 2009. All rights reserved.
Product data sheet Rev. 07 — 25 February 2009 6 of 48
NXP Semiconductors
PCF8566
Universal LCD driver for low multiplex rates
[1] The substrate (rear side of the die) is wired to V
DD
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 I
2
C-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 V
SS
. The only other connections required to complete the system are the
power supplies (pins V
DD
, V
SS
and V
LCD
) and the LCD panel selected for the application.
BP0 13 LCD backplane outputs
BP2 14
BP1 15
BP3 16
S0 to S23 17 to 40 LCD segment outputs
Table 3. Pin description
…continued
Symbol Pin Description
Table 4. Display configurations
Backplanes Elements 7-segment numeric 14-segment numeric Dot matrix
Digits Indicator
symbols
Characters Indicator
symbols
4 96 12 12 6 12 96 (4 × 24)
3729941672 (3× 24)
248663648 (2× 24)
1243311024
