I2C bus buffer and multiplexer — what it does for your bus
The NXP PCA9641PWJ is a 2-channel I2C bus buffer and multiplexer in a 16-TSSOP package. It sits between a master I2C controller and two downstream bus segments, buffering the clock and data lines while providing capacitive isolation.
Supply voltage and temperature — where it fits
The -40°C low end covers cold-start conditions in unheated enclosures. The 100 mA supply current is the total budget for the device itself plus whatever pull-up current the bus segments draw through the internal buffer.
Two channels — segmenting the I2C bus
With two channels, the PCA9641PWJ lets you isolate and independently enable two downstream I2C buses from a single master. This is useful when one segment has a device with a different supply voltage, a high capacitive load, or a device that could hang the bus. The input capacitance of 6 pF is low enough that it does not significantly load the upstream bus, even when both channels are disabled.
Package and mounting — reflow profile note
MSL level is not in the record, but TSSOP packages typically run MSL 1 or 2; if the reel's moisture barrier bag is intact, a bake before reflow is not normally needed, but confirm with the lot-specific label if the bag has been opened.