PCA9546APW,118

PCA9546APW,118 is a 4-channel I²C-bus switch with reset in a 16 pin TSSOP package. The SCL/SDA upstream pair fans out to four downstream pairs, or channels. Any individual SCx/SDx channel or combination of channels can be selected, determined by the contents of the programmable control register. An active LOW reset input allows the PCA9546A to recover from a situation where one of the downstream I²C-buses is stuck in a LOW state. Pulling RESET (active low) pin LOW resets I²C-bus state machine and causes all the channels to be deselected as does the internal POR function. The pass gates of the switches are constructed such that the VDD pin can be used to limit the maximum high voltage which is passed by the PCA9546A. This allows the use of different bus voltages on each pair, so that 1.8/2.5/3.3V parts can communicate with 5V parts without any additional protection. External pull-up resistors pull the bus up to the desired voltage level for each channel. All I/O pins are 5V tolerant.

• 1-of-4 bidirectional translating switches
• I²C-bus interface logic; compatible with SMBus standards
• 3 address pins allowing up to 8 devices on the I²C-bus
• Channel selection via I²C-bus, in any combination
• Power-up with all switch channels deselected
• Low Ron switches
• No glitch on power-up, supports hot insertion, low standby current
• Operating power supply voltage range of 2.3V to 5.5V and 5V tolerant input
• 0Hz to 400KHz clock frequency
• ESD protection exceeds 2000 V HBM per JESD22-A114 and 1KV CDM per JESD22-C101