General description
The PCA9506 provides 40-bit parallel input/output (I/O) port expansion for I2C-bus applications organized in 5 banks of 8 I/Os. At 5 V supply voltage, the outputs are capable of sourcing 10 mA and sinking 25 mA with a total package load of 800 mA to allow direct driving of 40 LEDs. Any of the 40 I/O ports can be configured as an input or output. Output ports are totem-pole and their logic state changes at the Acknowledge (bank change).

FEATUREs
■ Standard mode (100 kHz) and Fast mode (400 kHz) compatible I2C-bus serial interface
■ 2.3 V to 5.5 V operation with 5.5 V tolerant I/Os
■ 40 configurable I/O pins that default to inputs at power-up
■ Outputs:
  ◆ Totem-pole (10 mA source, 25 mA sink) with controlled edge rate output structure
  ◆ Active LOW output enable (OE) input pin 3-states all outputs
  ◆ Output state change on Acknowledge
■ Inputs:
  ◆ Open-drain active LOW interrupt (INT) output pin allows monitoring of logic level change of pins programmed as inputs
  ◆ Programmable Interrupt Mask Control for input pins that do not require an interrupt when their states change
  ◆ Polarity Inversion register allows inversion of the polarity of the I/O pins when read
■ Active LOW reset (RESET) input pin resets device to power-up default state
■ 3 programmable address pins allowing 8 devices on the same bus