PCA9537DP,118 (NXP)

The PCA9537DP is a 4-bit parallel Input/output (GPIO) Expander with interrupt and reset for I?C-bus/SMBus applications and was developed to enhance the NXP Semiconductors family of I?C-bus I/O expanders. The I/O expander provides a simple solution when additional I/O is needed for ACPI power switches, sensors, push-buttons, LEDs, fans, etc. It consists of a 4-bit configuration register (input or output selection), 4-bit input port register, 4-bit output port register and a 4-bit polarity inversion register (active HIGH or active LOW operation). The system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding input port or output port register. The polarity of the input port register can be inverted with the Polarity Inversion register. All registers can be read by the system master.