PCA9555AHF,128

The PCA9555AHF,128 is a 16-bit Input/output (GPIO) Expander with interrupt and weak pull-up resistors for I²C-bus/SMBus applications. The NXP I/O expander provides a simple solution when additional I/Os are needed while keeping interconnections to a minimum. In addition to providing a flexible set of GPIOs, the wide VDD range of 1.65 to 5.5V allows the PCA9555A to interface with next-generation microprocessors and microcontrollers where supply levels are dropping down to conserve power. It contains the PCA9555 register set of four pairs of 8-bit configuration, input, output and polarity inversion registers. The PCA9555A is a pin-to-pin replacement to the PCA9555 and other industry-standard devices. A more fully featured device, it is available with Agile I/O features. The expander open-drain interrupt (INT) output is activated when any input state differs from its corresponding input port register state and is used to indicate to the system master that an input state has changed.

• Low standby current consumption
• Schmitt-trigger action allows slow input transition and better switching noise immunity
• Open-drain active LOW interrupt output (INT)\ Internal power-ON reset
• Power-up with all channels configured as inputs with weak pull-up resistors
• No glitch on power-up
• Latched outputs with 25mA drive maximum capability for directly driving LEDs
• Latch-up performance exceeds 100mA per JESD 78, class II