SCPS275A July 2021 – December 2021 TCA9536
PRODUCTION DATA
The TCA9536 device is a 4-bit I/O expander for the I2C bus and is designed for 1.65-V to 5.5-V VCC operation. It provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface.
The TCA9536 consists of a configuration (input or output selection), Input Port, Output Port, and Polarity Inversion (active-high or active-low operation), and special function registers. At power-on, the I/Os are configured as inputs with a weak pull-up to VCC. The system controller can enable the I/Os as either inputs or outputs by writing to the I/O configuration register bits. The data for each input or output is kept in the corresponding Input or output register. The polarity of the Input Port register can be inverted with the Polarity Inversion register. There is an additional special function register that can be used to disable the internal pull-up resistors and P3 override to an INT output. All registers can be read by the system controller.
The TCA9536 open-drain interrupt output (when P3 is configured as INT in the special function register) is activated when any input differs from its corresponding Input Port register state and is used to indicate to the system controller that an input state has changed.
The system processor can reset the TCA9536 in the event of a timeout or other improper operation by using an I2C soft reset command, which puts the registers in their default state.
The device outputs (latched) have high-current drive capability for directly driving LEDs.