16-bit I2C and SMBus, low power I/O port with interrupt
• 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
• Offered in three different packages: SO24, TSSOP24, and
I2C/SMBus applications and was developed to enhance the Philips
family of I2C I/O expanders. The improvements include higher drive
capability, 5 V 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 PCA9535 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 PCA9535 is identical to the PCA9555 except for the removal of
the internal I/O pull-up resistor which greatly reduces power
consumption when the I/Os are held LOW.
The PCA9535 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 PCA9535 is the same as the PCA9554 allowing
up to eight of these devices in any combination to share the same
The PCA9535 is a 24-pin CMOS device that provide 16 bits of
General Purpose parallel Input/Output (GPIO) expansion for
24-Pin Plastic SO
-40 to +85 °C
24-Pin Plastic TSSOP
-40 to +85 °C
24-Pin Plastic HVQFN
-40 to +85 °C
Standard packing quantities and other packing 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.
2003 Jun 27