More than one RHT sensor is needed on a single I2C bus, however the I2C addresses are the same. How can two or more RHT sensors be used on the same I2C bus?
Answer
The RHT sensors do not have a programmable I2C address. Using a multiplexer and a device select line, multiple RHT sensors can use the same I2C bus. A single NMOS is placed on the SDA line with the drain on the host side and the source on the slave side. 10k pull-up resistors should be placed on both side of the NMOS. The MCU can control the SDA line by the device select.
Sensors Knowledge Base
Multi RH/T Sensors w/ Same I2C Address