Alternatively Analog Devices offers a protocol conversion device like an I2C to 1-Wire bridge. Most 1-Wire Slave devices are parasitically powered and do not need an external supply voltage. Power for device operation is derived from an internal power storage capacitor which stores charge when the 1-Wire line is idle. The Host or Master communicates digitally with the 1-Wire Slave using controlled low time duration pulses or time slots. All 1-Wire devices have an internal time base that is synchronized to the falling edge of the Master generated timing.