TIDUC26A April 2022 – April 2024
The PCA9543A is a dual bidirectional translating switch controlled by the I2C bus. The SCL/SDA upstream pair fans out to two downstream pairs, or channels. Either individual SCn/SDn channel or both channels can be selected, determined by the contents of the programmable control register. Two interrupt inputs (INT1– INT0), 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 both of the channels to be deselected, as does the internal power-on reset function. This device is used in this reference design to allow communication to both LDC3114-Q1 devices since both devices share the same I2C address.