Two-Channel I2C-Bus Switch With Interrupt Logic And Reset

The PCA9543A is a bidirectional translating Switch controlled by the I2C bus. The SCL/SDA upstream pair fans out to two downstream pairs, or channels. Any individual SCn/SDn channel or combination of channels CAN be selected, determined by the contents of the programmable control Register Two interrupt inputs (INT0-INT1), one for each of the downstream pairs, are provided. One interrupt output (INT) acts as an AND of the two interrupt inputs. An active-low reset (RESET) input allows the PCA9543A to recover from a situation where one of the downstream I2C buses is stuck in a low state. Pulling RESET low resets the I2C state machine and causes all the channels to be deselected, as does the internal power-on reset function. By Texas Instruments