The PCA9306 level conversion module is a bidirectional voltage converter designed for I²C/SMBus, which can seamlessly connect different voltage devices from 1.2V to 5V, such as 3.3V MCU (such as STM32, ESP8266, ) and 5V sensors (such as OLED, , MPU6050). It uses TI () PCA9306 chip, which is stable and reliable, supports 400kHz high-speed I²C communication, does not require direction control, and is plug-and-play! Bidirectional conversion: Wide voltage supports any combination of 1.2V~5V (such as 3.3V↔5V, 1.8V↔3.3V), and efficiently manages bidirectional voltage conversion between 5V and 3.3V to reliable data transmission and device functionality. Easy to integrate: Integrated PCB, straight-in pin headers, convenient breadboard/ line connection, and compact breakout board design, which can be directly integrated into your existing projects without complicated wiring or setup. High compatibility: This PCA9306 I²C level converter module is designed for seamless communication between devices with different voltage levels. The dual-channel design can simultaneously convert the two I²C signal lines SCL (clock) and SDA (data), making it ideal for a variety of I²C applications. Wide application: Bidirectional automatic conversion, no additional control signals required, and automatic identification of data transmission direction are very suitable for developers using microcontrollers, sensors and other electronic components that need to adjust voltage levels. Chip model PCA9306DCUR (TI) Input voltage range 1.2V ~ 5V (VREF1 ≤ VREF2) Maximum frequency 400kHz (I²C Fast Mode) Conversion direction Bidirectional automatic switching Interface type I²C (SCL + SDA) Operating temperature -40°C ~ +85°C Pin definition VREF1 Low voltage side power supply (such as 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 VREF2 High voltage side power supply (such as 5V) EN Enable terminal (high level is valid, connected to VREF2 by default) Typical application scenarios for (5V) communicates with ESP8266/ (3.3V) 5V sensor (such as LCD1602) connected to 3.3V microcontroller (STM32) Mixed voltage I²C bus system (such as 1.8V sensor + 3.3V MCU) Notes on use Voltage rule: VREF1 ≤ VREF2 (e.g. VREF1 on the 3.3V side, VREF2 on the 5V side) Pull-up resistor: The module itself does not contain a pull-up resistor, and an external 4.7kΩ~10kΩ resistor must be connected according to the I²C bus voltage Enable pin (EN): If not used, it is recommended to connect to VREF2 (enabled by default) Color: As Shown Material: PCB Package Contents: 1 * PCA9306 Level Conversion Module 2 * Pin header (need to be soldered) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.