Step-adjustable integrated regulated power supply

Step-adjustable integrated regulated power supply

, the collector-emitter of the adjustment tube VTI is connected to a resistor R3, which is called the starting resistor , and its
power is relatively large. It has three functions in the circuit: first, it is the starting function when the power is turned on; second, it serves as the load of the rectifier circuit when the output terminal of the power supply is short-circuited ,
which can limit the current in the rectifier tube to protect the rectifier circuit ; third, it serves as a shunt for the adjustment tube Resistor; to reduce the power consumption of the adjustment tube.
    The figure shows a step-type adjustable integrated voltage regulator circuit, which uses a three-terminal integrated voltage regulator. When the position of switch Sl is changed,
6 kinds of DC voltages can be output.