pcf8535 NXP Semiconductors, pcf8535 Datasheet - Page 5

• Manufacturer Part Number: pcf8535
• Description: 65 X 133 Pixel Matrix Driver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
5.1
5.1.1
The on-chip oscillator provides the display clock for the
system; it requires no external components. Alternatively,
an external display clock may be provided via the OSC
input. The OSC input must be connected to V
when not in use. During power-down additional current
saving can be made if the external clock is disabled.
5.1.2
The on-chip Power-on reset initializes the chip after
power-on or power failure.
5.1.3
The I
address, commands and display data bytes. It performs
the conversion of the data input (serial-to-parallel).
The PCF8535 acts as an I
cannot initiate bus communication.
5.1.4
Input filters are provided to enhance noise immunity in
electrically adverse environments. RC low-pass filters are
provided on the SDA, SCL and RES lines.
2001 Nov 07
65
2
C-bus controller detects the I
Block diagram functions
O
P
I
I
2
NPUT FILTERS
133 pixel matrix driver
OWER
C-
SCILLATOR
BUS CONTROLLER
-
ON RESET
2
C-bus slave and therefore
2
C-bus protocol, slave
DD1
or V
SS1
5
5.1.5
The PCF8535 contains a 65
stores the display data. The RAM is divided into 9 banks of
133 bytes. The last bank is used for icon data and is only
one bit deep. During RAM access, data is transferred to
the RAM via the I
correspondence between the X address and the column
output number.
5.1.6
The timing generator produces the various signals
required to drive the internal circuitry. Internal chip
operation is not affected by operations on the data bus.
5.1.7
The address counter sends addresses to the Display Data
RAM (DDRAM) for writing.
5.1.8
The display is generated by continuously shifting rows of
RAM data to the dot matrix LCD via the column outputs.
The display status (all dots on or off, normal or inverse
video) is set via the I
D
T
A
D
IMING GENERATOR
DDRESS COUNTER
ISPLAY DATA
ISPLAY ADDRESS COUNTER
2
C-bus interface. There is a direct
2
C-bus.
RAM
133 bit static RAM which
Product specification
PCF8535