PCA9548

Features:

• 1-of-8 bi-directional translating switches
• I²C interface logic; compatible with SMBus standards
• Active LOW Reset Input
• 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 RdsON switches
• Allows voltage level translation between 1.8 V, 2.5 V, 3.3 V and 5 V buses
• No glitch on power-up
• Supports hot insertion
• Low stand-by current
• Operating power supply voltage range of 2.3 V to 5.5 V
• 5 V tolerant Inputs
• 0 kHz to 400 kHz clock frequency
• ESD protection exceeds 2000 V HBM per JESD22-A114, 150 V MM per JESD22-A115 and 1000 V per JESD22-C101
• Latchup testing is done to JESDEC Standard JESD78 which exceeds 100 mA
• Packages offered: SO24, TSSOP24


Pinout




Specifications

SYMBOL	PARAMETER	CONDITIONS	MIN	MAX	UNIT
VDD	DC supply voltage		0.5 to +7.0	6.0	V
VI	DC supply voltage		0.5 to +7.0	5.5	V
II	DC output current		±20	±25	mA
IO	DC output current		±25	100	mA
IDD	Supply current		±100	400	mA
ISS	Supply current		±100	+150	mA
Ptot	total power dissipation		400	+85	mW
Tstg	Storage temperature range		60 to +150		°C
Tamb	Operating ambient temperature		40 to +85		°C

Description

The PCA9548 is a octal bi-directional translating switch controlled by the I2C-bus. The SCL/SDA upstream pair fans out to eight 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 PCA9548 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 state machine and causes all the channels to be deselected as does the internal power on reset function.

The pass gates of the switches are constructed such that the VDD pin can be used to limit the maximum high voltage which will be passed by the PCA9548. This allows the use of different bus voltages on each pair, so that 1.8 V, 2.5 V, or 3.3 V parts can communicate with 5 V 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 5 V tolerant.