PCA9541A - NXP Semiconductors

PCA9541A 2-to-1 I2C-bus master selector

The PCA9541A is a 2-to-1 I2C-bus master selector designed for high reliability dual master I2C-bus applications where system operation is required, even when one master fails or the controller card is removed for maintenance. The two masters (for example, primary and back-up) are located on separate I2C-buses that connect to the same downstream I2C-bus slave.

Features

 2-to-1 bidirectional master selector
 I2C-bus interface logic; compatible with SMBus standards
 PCA9541A/01 powers up with Channel 0 selected
 PCA9541A/03 powers up with no channel selected and either master can take control of the bus
 Active LOW interrupt input
 2 active LOW interrupt outputs
 Active LOW reset input
 4 address pins allowing up to 16 devices on the I2C-bus
 Channel selection via I2C-bus
 Bus initialization/recovery function
 Bus traffic sensor
 Low Ron switches
 Allows voltage level translation between 1.8 V, 2.5 V, 3.3 V and 5 V buses
 No glitch on power-up
 .