This 4-bit I/O expander for the two-line bidirectional bus
(I2C) is designed for 2.3-V to 5.5-V VCC
operation. It provides general-purpose remote I/O expansion for most microcontroller families via
the I2C interface [serial clock (SCL), serial data (SDA)].
The PCA9536 features 4-bit Configuration (input or output selection), Input Port, Output
Port, and Polarity Inversion (active high or active low) registers. At power on, the I/Os are
configured as inputs with a weak pullup to VCC. However, the system master
can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. If no
signals are applied externally to the PCA9536, the voltage level is 1, or high, because of the
internal pullup resistors. The data for each input or output is stored in the corresponding Input
Port or Output Port register. The polarity of the Input Port register can be inverted with the
Polarity Inversion register. All registers can be read by the system master.
The system master can reset the PCA9536 in the event of a timeout or other improper
operation by utilizing the power-on reset feature, which puts the registers in their default state
and initializes the I2C/SMBus state machine.
The device's outputs (latched) have high-current drive capability for directly driving
LEDs. It has low current consumption.
View datasheet View product folder