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Philips Semiconductors
Product data
PCA9555
16-bit I2C and SMBus I/O port with interrupt
2
2002 Jul 26
853-2252 28672
FEATURES
Operating power supply voltage range of 2.3 V–5.5 V
5 V tolerant I/Os
Polarity inversion register
Active low interrupt output
Low stand-by current
Noise filter on SCL/SDA inputs
No glitch on power-up
Internal power-on reset
16 I/O pins which default to 16 inputs
0 to 400 kHz clock frequency
ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V
MM per JESD22-A115, and 1000 V CDM per JESD22-C101
Latch-up testing is done to JESDEC Standard JESD78 which
exceeds 100 mA
Four packages offered: SO24, SSOP24, TSSOP24, and
HVQFN24
DESCRIPTION
The PCA9555 is a 24-pin CMOS device that provide 16 bits of
General Purpose parallel Input/Output (GPIO) expansion for
I2C/SMBus applications and was developed to enhance the Philips
family of I
@C I/O expanders. The improvements include higher drive
capability, 5V I/O tolerance, lower supply current, individual I/O
configuration, and smaller packaging. I/O expanders provide a
simple solution when additional I/O is needed for ACPI power
switches, sensors, pushbuttons, LEDs, fans, etc.
The PCA9555 consist of two 8-bit Configuration (Input or Output
selection); Input, Output and Polarity inversion (Active high or Active
low operation) registers. The system master can enable the I/Os as
either inputs or outputs by writing to the I/O configuration bits. The
data for each Input or Output is kept in the corresponding Input or
Output register. The polarity of the read register can be inverted with
the Polarity Inversion Register. All registers can be read by the
system master. Although pin to pin and I2C address compatible with
the PCF8575, software changes are required due to the
enhancements and are discussed in Application Note AN469.
The PCA9555 open-drain interrupt output is activated when any
input state differs from its corresponding input port register state and
is used to indicate to the system master that an input state has
changed. The power-on reset sets the registers to their default
values and initializes the device state machine.
Three hardware pins (A0, A1, A2) vary the fixed I2C address and
allow up to eight devices to share the same I2C/SMBus. The fixed
I2C address of the PCA9555 is the same as the PCA9554 allowing
up to eight of these devices in any combination to share the same
I2C/SMBus.
ORDERING INFORMATION
PACKAGES
TEMPERATURE
RANGE
ORDER CODE
TOPSIDE MARK
DRAWING NUMBER
24-Pin Plastic SO
–40 to +85
°C
PCA9555D
SOT137-1
24-Pin Plastic SSOP
–40 to +85
°C
PCA9555DB
PCA9555
SOT340-1
24-Pin Plastic TSSOP
–40 to +85
°C
PCA9555PW
PCA9555
SOT355-1
24-Pin Plastic HVQFN
–40 to +85
°C
PCA9555BS
9555
SOT616-1
Standard packing quantities and other packaging data are available at www.philipslogic.com/packaging.
I2C is a trademark of Philips Semiconductors Corporation.
SMBus as specified by the Smart Battery System Implementers Forum is a derivative of the Philips I2C patent.