PCA9544

Features:

• 1-of-4 bi-directional translating multiplexer
• Channel selection via I²C bus
• Operating supply voltage 2.5 to 3.6 V
• Operating temperature range 0°C to 70°C
• Power-up with all multiplexer channels deselected
• 3 address pins, allowing up to 8 devices on the I2C bus
• Low on resistance


Pinout




Specifications

symbol	partameter	conditions	RATINGMINMAX		unit
VDD	DC supply voltage		-0.5to +7.0		V
VI	DC input voltage		-0.5 to+7.0		V
Ii	DC input current		±20		MA
IO	DC output current		±25		MA
I DC	DC Supply current		±100		MA
ISS	DC Supply current		±100		MA
Ptot	total power dissipation		400		MW
Tstg	Storage temperature range		60 to+150		°C
Tamb	Operating ambient temperature		0to70		°C

Description

The PCA9544 is a 1-of-4 bi-directional translating multiplexer, controlled via the I2C bus. The SCL/SDA upstream pair fans out to four SCx/SDx downstream pairs, or channels. Only one SCx/SDx channel of PCA9544 is selected at a time, determined by the contents of the programmable control register. Four interrupt inputs, one for each of the SCx/SDx downstream pair, are provided. One interrupt output, which acts as an AND of the four interrupt inputs, is provided. All I/O pins are 5 V tolerant.

The pass gates of PCA9544 of the multiplexer are constructed such that the VDD pin can be used to limit the maximum high voltage which will be passed by the PCA9544. This allows the use of different bus voltages on each SCx/SDx pair, so that 3.3 V parts can communicate with 5 V parts without any additional protection. External pull-up resistors can pull the bus up to the desired voltage level for this channel.