Philips Semiconductors
LCD direct/duplex driver with
I2C-bus interface
Product specification
PCF8577C
1 FEATURES
• Direct/duplex drive modes with up to
32/64 LCD-segment drive capability per device
• Operating supply voltage: 2.5 to 6 V
• Low power consumption
• I2C-bus interface
• Optimized pinning for single plane wiring
• Single-pin built-in oscillator
• Auto-incremented loading across device subaddress
boundaries
• Display memory switching in direct drive mode
• May be used as I2C-bus output expander
• System expansion up to 256 segments
• Power-on reset blanks display
• I2C-bus address: 0111 0100.
2 GENERAL DESCRIPTION
The PCF8577C is a single chip, silicon gate CMOS circuit.
It is designed to drive liquid crystal displays with up to
32 segments directly, or 64 segments in a duplex
configuration.
The two-line I2C-bus interface substantially reduces wiring
overheads in remote display applications. I2C-bus traffic is
minimized in multiple IC applications by automatic address
incrementing, hardware subaddressing and display
memory switching (direct drive mode).To allow partial VDD
shutdown the ESD protection system of the SCL and SDA
pins does not use a diode connected to VDD.
3 ORDERING INFORMATION
TYPE NUMBER
PCF8577CP
PCF8577CT
PCF8577CT
PCF8577CU/10
NAME
DIP40
VSO40
−
−
PACKAGE
DESCRIPTION
plastic dual in-line package; 40 leads (600 mil)
plastic very small outline package; 40 leads
VS040 in blister tape
chip on film-frame-carrier (FFC)
VERSION
SOT129-1
SOT158A
−
−
4 BLOCK DIAGRAM
39
SCL
I 2C - BUS
40
SDA
INPUT
FILTERS
I 2C - BUS
CONTROLLER
SEGMENT BYTE
REGISTERS
AND
MULTIPLEX
LOGIC
V DD
VSS
35
POWER -
ON
RESET
38
PCF8577C
CONTROL REGISTER
AND
COMPARATOR
Fig.1 Block diagram.
1
S32
BACKPLANE
AND
SEGMENT
DRIVERS
32
S1
33
BP1
34
A2/BP2
36
A1
37
A0/OSC
OSCILLATOR
AND
DIVIDER
MGA727
1998 Jul 30
3