2-Bit Bidirectional I2C Bus and SMBus Voltage-Level Shifter - PCA9306


2-Bit Bidirectional I2C Bus and SMBus Voltage-Level Shifter


The PCA9306 is a dual bidirectional I2C and SMBus voltage-level translator, with an enable (EN) input, is operational from 1.2-V to 3.3-V VREF1 and 1.8-V to 5.5-V VREF2.

The PCA9306 allows bidirectional voltage translations between 1.2 V and 5 V, without the use of a direction pin. The low ON-state resistance (RON) of the switch allows connections to be made with minimal propagation delay. When EN is high, the translator switch is ON, and the SCL1 and SDA1 I/O are connected to the SCL2 and SDA2 I/O, respectively, allowing bidirectional data flow between ports. When EN is low, the translator switch is off, and a high-impedance state exists between ports.

In addition to voltage translation, the PCA9306 can be used to isolate a 400-kHz bus from a 100-kHz by controlling the EN pin.


  • 2-Bit Bidirectional Translator for SDA and SCL Lines in Mixed-Mode
    I2C Applications
  • I2C and SMBus Compatible
  • Less Than 1.5-ns Maximum Propagation Delay to Accommodate Standard-
    Mode and Fast-Mode I2C Devices and Multiple Masters
  • Allows Voltage-Level Translation Between
    • 1.2-V VREF1 and 1.8-V, 2.5-V, 3.3-V,
      or 5-V VREF2
    • 1.8-V VREF1 and 2.5-V, 3.3-V, or 5-V
    • 2.5-V VREF1 and 3.3-V or 5-V
    • 3.3-V VREF1 and 5-V VREF2
  • Provides Bidirectional Voltage Translation With No Direction Pin
  • Low 3.5-Ω ON-State Connection Between Input and Output Ports Provides
    Less Signal Distortion
  • Open-Drain I2C I/O Ports (SCL1, SDA1, SCL2, and SDA2)
  • 5-V Tolerant I2C I/O Ports to Support Mixed-Mode Signal
  • High-Impedance SCL1, SDA1, SCL2, and SDA2 Pins for EN = Low
  • Lock-Up-Free Operation for Isolation When EN = Low
  • Flow-Through Pinout for Ease of Printed Circuit Board Trace Routing
  • 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)

View more

Parametrics Compare all products in I2C Special Function

No. of Outputs
Operating Temperature Range (C)
Max Frequency (kHz)
I2C Address
Approx. Price (US$)
Special Features
PCA9306 PCA9306-Q1 TCA9406
2     2     2    
-40 to 85     -40 to 105
-40 to 85    
-40 to 85    
Catalog     Automotive     Catalog    
400     400     1000    
Voltage Translator     Voltage Translator     I2C Voltage Level Translator    
N/A     N/A     N/A    
0.24 | 1ku     0.28 | 1ku     0.38 | 1ku    
Enable Pin
Open-Drain I/O Type
5V Tolerant I/O    
Enable Pin
Open-Drain I/O Type
5V Tolerant I/O    
Enable Pin
Open-Drain I/O Type
5V Tolerant I/O
Push-Pull I/O Type    

Other qualified versions of PCA9306

Version Part Number Definition
Automotive PCA9306-Q1 Q100 devices qualified for high-reliability automotive applications targeting zero defects
Click Here