PCA9557DR TI I/O Expanders

The PCA9557DR is an 8-bit I2C-bus and SMBus I/O expander from Texas Instruments featuring a hardware reset input for returning the device to its default state. It operates over a supply voltage range of 2.3V to 5.5V and supports both 100-kHz (Standard-mode) and 400-kHz (Fast-mode) clock frequencies. The device provides 8 general-purpose I/O pins that can be individually configured as input or output via an I/O direction register. Key features include open-drain active-low interrupt output for change detection, polarity inversion register for inverting the polarity of the input port register, internal power-on reset, and latched outputs with high-current drive capability for directly driving LEDs. The hardware reset input allows the device to be reset to its default power-on state without cycling the power supply, providing additional flexibility in system design. Housed in a 16-pin SOIC (D) package, it operates over -40°C to 85°C. Applications include servers, routers, personal computers, industrial automation, and GPIO-limited processor systems requiring 8-bit I/O expansion with hardware reset capability. In stock at HL Electronics – request a quote for fast delivery.