Image Number 2 for United States Patent #7567113.
A single signal trace can be multiplexed between a circuit that provides a reference voltage and another circuit that is not operational while the reference voltage is needed. Fewer signal connections will be needed due to the multiplexing. As one possible example, a clock signal that is used at initial power up of an electrical circuit can later be used as a reference voltage. In one specific example, a signal line is connected from one electronic device to a second electronic device. The signal line is connected to a clock input of a circuit and an input to an amplifier. When the devices first power up a clock signal is active on the signal line and is used to the clock input. When the clock signal is no longer needed the signal can be used to drive the amplifier to create a reference voltage.