I2C-bus Multiplexer, Single data line, serial communication bus invented

 PCA9532 Series 5.5 V 350 uA 400kHz SMT 16-bit I2C-bus LED Dimmer - TSSOP-24

https://www.futureelectronics.com/p/semiconductors--comm-products--i2c/pca9532pw-118-nxp-5033862