1. General description
The PCA9536 is an 8-pin CMOS device that provides 4 bits of General Purpose parallel
Input/Output (GPIO) expansion for I
2
C-bus/SMBus applications and was developed to
enhance the NXP Semiconductors family of I
2
C-bus I/O expanders. I/O expanders
provide a simple solution when additional I/O is needed for ACPI power switches,
sensors, push buttons, LEDs, fans, etc.
The PCA9536 consists of a 4-bit Configuration register (input or output selection), 4-bit
Input Port register, 4-bit Output Port register and a 4-bit Polarity Inversion register
(active HIGH or active LOW operation). 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 Port or Output Port register. The polarity of the read
register can be inverted with the Polarity Inversion register. All registers can be read by
the system master.
The power-on reset sets the registers to their default values and initializes the device state
machine.
The I
2
C-bus address is fixed and allows only one device on the same I
2
C-bus/SMBus.
2. Features and benefits
4-bit I
2
C-bus GPIO
Operating power supply voltage range of 2.3 V to 5.5 V
5 V tolerant I/Os
Polarity Inversion register
Low standby current
Noise filter on SCL/SDA inputs
No glitch on power-up
Internal power-on reset
4 I/O pins which default to 4 inputs with 100 k internal pull-up resistor
0 Hz 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 JEDEC Standard JESD78 which exceeds 100 mA
Packages offered: SO8, TSSOP8 (MSOP8), HVSON8
PCA9536
4-bit I
2
C-bus and SMBus I/O port
Rev. 6 — 7 November 2017 Product data sheet
