●The PCAL6408AHKX is an 8-bit I/O Expander that provides remote I/O expansion for most microcontroller families via the I²C-bus interface. 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, it simplifies interconnection of a processor running at one voltage level to I/O devices operating at a different (usually higher) voltage level. The PCAL6408A has built-in level shifting feature that makes this device extremely flexible in mixed signal environments where communication between incompatible I/O voltages is required. Its wide VDD range of 1.65 to 5.5V on the dual power rail allows seamless communications with next-generation low voltage microprocessors and microcontrollers on the interface side (SDA/SCL) and peripherals at a higher voltage on the port side.
● 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
● No glitch on power-up
● Latched outputs with 25mA drive maximum capability for directly driving LEDs
● Latch-up performance exceeds 100 mA per JESD 78, class II
● Bank selectable push-pull or open-drain output stages
● Read-only register identifies the source of an interrupt
● Input port register values changes are kept until the input port register is read
● Floating input or pull-up/pull-down resistor enable
● Mask prevents the generation of the interrupt when input changes state
● 100kR Pull-up/down resistor
