Voltage or tap the source whilst the power source dc voltage or installed examples. It is designed by combining an unregulated power supply with a transistor circuit operating in the saturation region. The menu system also includes settings, like and Output Recall, that determine how the instrument initializes itself when it is turned on. Scheme report of the power supply with test results performed by safety agencies, such as UL, CSA, or TUV. One problem with such an arrangement is if one light bulb burns out, then it acts like a switch and turns off the whole circuit. DC-DC Power Supply Guide For SFFPC's Lazer3D. Voltage and Current Sources Independent and Dependent.