Bidirectional I2C Level Shifter Module with 5V and 3.3V Support for UART and I2C Communication Protocols

The PCA9306 level conversion module is a bidirectional voltage converter designed for I²C/SMBus applications. It connects devices operating at different voltage levels ranging from 1.2V to 5V, such as 3.3V microcontrollers (e.g., STM32, ESP8266, Raspberry Pi) and 5V sensors (e.g., OLED, BMP180, MPU6050). It uses the Texas Instruments PCA9306 chip, offering stable and reliable performance with support for 400 kHz I²C Fast Mode communication. No direction control is required — operation is fully automatic and plug-and-play. Bidirectional conversion: Supports any voltage combination between 1.2V and 5V (e.g., 3.3V ↔ 5V, 1.8V ↔ 3.3V), enabling efficient voltage translation while ensuring reliable data transmission. Easy integration: Features a compact PCB breakout board with straight pin headers, compatible with breadboards and standard jumper wires for simple prototyping and system integration. High compatibility: Designed specifically for I²C bus level shifting. Dual-channel architecture simultaneously translates both SCL (clock) and SDA (data) lines. Wide application: Suitable for use with microcontrollers, sensors, and other electronic components requiring voltage-level translation on I²C buses. Chip model: PCA9306DCUR (Texas Instruments) Input voltage range: 1.2V to 5V (VREF1 ≤ VREF2) Maximum frequency: 400 kHz (I²C Fast Mode) Conversion direction: Bidirectional, automatic Interface type: I²C (SCL + SDA) Operating temperature: –40°C to +85°C Pin definitions: VREF1 — Low-voltage-side power supply (e.g., 3.3V) SCL1 — Low-voltage-side I²C clock line SDA1 — Low-voltage-side I²C data line GND — Ground SDA2 — High-voltage-side I²C data line SCL2 — High-voltage-side I²C clock line