PCA9540

INTEGRATED CIRCUITS PCA9540 2-channel I2C multiplexer Product specification 1999 Dec 15 Philips Semiconductors Philips Semiconductors Product specification 2-channel I2C multiplexer PCA9540 FEATURES 1-of-2 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 Low on resistance DESCRIPTION The PCA9540 is a 1-of-2 bi-directional translating multiplexer, controlled via the I2C bus. The SCL/SDA upstream pair fans out to two SCx/SDx downstream pairs, or channels. Only one SCx/SDx channel is selected at a time, determined by the contents of the programmable control register. The pass gates 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 PCA9540. 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. PIN CONFIGURATION SCL SDA VDD SD0 1 2 3 4 8 7 6 5 SC1 SD1 VSS SC0 SW00491 PIN DESCRIPTION PIN NUMBER 1 2 3 4 5 6 7 8 SYMBOL SCL SDA VDD SD0 SC0 VSS SD1 SC1 FUNCTION Serial clock line Serial data line Supply voltage Serial data 0 Serial clock 0 Supply ground Serial data 1 Serial clock 1 ORDERING INFORMATION PACKAGES 8-Pin Plastic SO 8-Pin Plastic TS...