I2C level module, 3V to 5V, 5V to 3V for. 3A connected 3V system. 3B connected 3V system. GND connected 3V system GND. 5A connected 5V system. 5B connected 5V system. GND connected 5V system GND. Many channels I2C level module, IIC SPI TTL level module, compatible with 5-3v system.
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