Today I finished my self designed I²C Hub with an integrated level shifter.
As level shifter I used the “4-channel I2C-safe Bi-directional Logic Level Converter – BSS138” from adafruit. Now it is possible to connect to the hub four 3.3V I²C devices plus the Raspberry Pi as 3.3V device and five 5.0V I²C devices and the Raspberry Pi as master. For the first test I connectec two ultrasonic sensors SRF08 as shown in the picture below on the 5.0V side of the board.
The picture below shows the I²Cdetect command executed in the terminal window. Both connected SRF08 ultrasonic sensors where found on the bus.
The hub is perfect for my robot car I actual build. With the 3.3V on one side and 5.0V on the other side I am now able to use 5.0V devices as well on my Raspberry Pi which is initially a 3.3V device.