DESCRIPTION
The PCA9556 is a silicon CMOS circuit which provides parallel input/output expansion for SMBus applications.

FEATURES
• SMBus compliance with fixed 3.3V voltage levels
• Operating power supply voltage range of 3.0V – 3.6V
• Active high polarity inverter register
• Write protect register
• Active low reset pin
• Low leakage current on power-down
• Noise filter on SCL/SDA inputs
• No glitch on power-up
• Internal power-on reset
• 8 I/O pins which default to 8 inputs
• High impedance open drain on I/O