Interface - I/O Expanders are specialized Integrated Circuits (ICs) designed to enable a microcontroller or microprocessor to interface with a larger number of input/output (I/O) devices than its available pins would normally allow. By acting as a bridge, they facilitate communication between the processor and multiple peripherals through a more compact connection, using protocols such as I2C or SPI. The main function of I/O expanders is to provide additional ports, which can be configured as inputs to read sensors, buttons, and switches, or as outputs to control LEDs, displays, or other actuators.
The primary uses of these expanders are found in systems where the control unit has limited I/O pins and cannot be connected directly to all the desired peripherals. Characteristics of I/O expanders include the ability to operate on low power, support various communication protocols, and offer features like interrupt generation for efficient data handling. They are used extensively in applications including smartphones, home automation systems, automotive electronics, and industrial controls. Notable manufacturers of Interface - I/O Expanders include Texas Instruments, Microchip Technology, NXP Semiconductors, STMicroelectronics, and Analog Devices.