PCA9544A

Features:

*1-of-4 bi-directional translating multiplexer
*I²C interface logic; compatible with SMBus
*4 Active-LOW Interrupt Inputs
*Active-LOW Interrupt Output
*3 address pins allowing up to 8 devices on the I²C-bus
*Channel selection via I²C-bus
*Power-up with all multiplexer 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 to 400 kHz clock frequency
*ESD protection exceeds 2000 V HBM per JESD22-A114,200 V MM per JESD22-A115 and 1000 V per JESD22-C101
*Latchup testing is done to JESDEC Standard JESD78 which exceeds 100 mA
*Three packages offered: SO20, TSSOP20, and HVQFN20


Pinout




Specifications

SYMBOL	PARAMETER	CONDITIONS	RATING	UNIT
VDD	DC supply voltage		0.5 to +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
IDD	Supply current		±100	mA
ISS	Supply current		±100	mA
Ptot	total power dissipation		400	mW
Tstg	Storage temperature range		60 to +150	°C
Tamb	Operating ambient temperature		40 to +85	°C

Description

The PCA9544A 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 PCA9544A is selected at a time, determined by the contents of the programmable control register. Four interrupt inputs, INTO toINT3 , one for each of the SCx/SDx downstream pairs, are provided. One interrupt output, INT , which acts as an AND of the four interrupt
inputs, is provided.

A power-on reset function of PCA9544A puts the registers in their default state and initializes the I²C state machine with no channels selected.

The pass gates of the multiplexer are constructed such that the V_DD pin can be used to limit the maximum high voltage which will be passed by the PCA9544A. PCA9544A allows the use of different bus voltages on each SCx/SDx 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.