TI TCA9543APWR

The TCA9543A is a dual bidirectional translating switch controlled by the I²C bus. The serial clock/serial data (SCL/SDA) upstream pair is expanded to 2 downstream pairs, or channels. Any individual SCn/SDn channel or both channels can be selected based on the contents of the programmable control register. Two interrupt inputs (INT1–INT0) are provided, one for each downstream pair. A single interrupt output (INT) serves as the AND of the two interrupt inputs. An active-low reset (RESET) input allows the TCA9543A to recover from a situation where one of the downstream I²C buses is stuck low. Pulling RESET low resets the I²C state machine and deselects both channels, identical in function to the internal power-on reset. Pass-gate transistors are built into the switch so that the VCC pin can be used to limit the maximum high voltage passed by the TCA9543A. This allows different bus voltages to be used on each pair, enabling 1.8V, 2.5V, or 3.3V devices to communicate with 5V devices without any additional protection. For each channel, external pull-up resistors pull the bus voltage up to the desired level. All I/O pins are 5.5V tolerant.

• 2-of-1 bidirectional switching, I²C bus and SMBus compatible
• Two active-low interrupt inputs
• Active-low interrupt output
• Active-low reset input
• Two address pins, supporting up to four TCA9543A devices on the I²C bus
• Channel selection via I²C bus, any combination
• All switch channels deselected at power-up
• Low RON switches
• Voltage level translation between 1.8V, 2.5V, 3.3V, and 5V buses
• No glitch at power-up
• Hot insertion supported
• Low standby current
• Operating supply voltage range: 1.65V to 5.5V
• 5.5V tolerant inputs
• Clock frequency: 0 to 400kHz
• Latch-up performance exceeds 100mA per JESD78
• ESD protection exceeds JESD 22 requirements
  • 4000V Human Body Model (A114-A)
  • 1500V Charged Device Model (C101)

• Servers
• Routers (telecom switching equipment)
• Factory automation
• Products with I2C slave address conflicts (multiple identical temperature sensors)