8-channel I2C-bus multiplexer with reset

Allowing immediate communication between the master and downstream devices, the PCA9547 powers up with Channel 0 connected. An active LOW reset input allows the PCA9547 to recover from a situation where one of the downstream I²C-buses is stuck in a LOW state. Pulling the RESET pin LOW resets the I²C-bus state machine causing all the channels to be deselected, except Channel 0 so that the master can regain control of the bus.

It is an octal bidirectional translating multiplexer controlled by the I²C-bus. The SCL/SDA upstream pair fans out to eight downstream pairs, or channels but only one SCx/SDx channel can be selected at a time, determined by the contents of the programmable control register.

Product Block Diagram

Product Block Diagram

Why Used

  • Operating power supply voltage range of 2.3 V to 5.5 V
  • 5 V tolerant inputs
  • 0 Hz to 400 kHz clock frequency
  • ESD protection exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101
  • Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA

Where Used

  • Basestation – discretes focus / transceiver board
  • Digital media adapters
  • LCD display – discretes focus
  • PCI analog / DVB-T stereo TV receiver
  • UMA-enabled GSM/GPRS/EDGE VAS Phone (6100)

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