Low Voltage I2C Switch 8-CH 24-Pin VQFN T/R

The TCA9548A device has eight bidirectional translating switches that can be controlled through the I2C bus. The SCL/SDA upstream pair fans out to eight downstream pairs, or channels. Any individual SCn/SDn channel or combination of channels can be selected, determined by the contents of the programmable control register.The system master can reset the TCA9548A in the event of a time-out or other improper operation by asserting a low in the RESET input. Similarly, the power-on reset deselects all channels and initializes the I2C/SMBus state machine. Asserting RESET causes the same reset and initialization to occur without powering down the part.The pass gates of the switches are constructed so that the VCC pin can be used to limit the maximum high voltage, which is passed by the TCA9548A. Limiting the maximum high voltage allows the use of different bus voltages on each pair, so that 1.8-V or 2.5-V or 3.3-V parts can communicate with 5-V parts, without any additional protection. External pullup resistors pull the bus up to the desired voltage level for each channel. All I/O pins are 5-V tolerant.

1-to-8 Bidirectional Translating Switches

I²C Bus and SMBus Compatible

Active-Low Reset Input

Three Address Pins, Allowing up to Eight TCA9548A
Devices on the I²C Bus

Channel Selection Through an I²C Bus,
In Any Combination

Power Up With All Switch Channels Deselected

Low R_ON 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 Standby Current

Operating Power-Supply Voltage Range of
1.65-V to 5.5-V

5-V Tolerant Inputs

0- to 400-kHz Clock Frequency

Latch-Up Performance Exceeds 100 mA Per JESD 78,
Class II

ESD Protection Exceeds JESD 22

• ±2000-V Human-Body Model (A114-A)
• 200-V Machine Model (A115-A)
• ±1000-V Charged-Device Model (C101)