摘要 |
<p>A DC voltage-limiting circuit generally includes first, second, and third transistors. The first transistor is connected between a voltage input terminal and a voltage output terminal. The first transistor has a collector connected to the voltage input terminal, an emitter connected to the voltage output terminal, and a base connected to the voltage input terminal via a first resistor. The second transistor has a base connected to the voltage input terminal via a first voltage regulator and a second resistor, a collector connected to the base of the first transistor, and an emitter connected to the voltage output terminal. The third transistor has a collector connected to the base of the first transistor via a third resistor, an emitter grounded, and a base connected to the voltage output terminal via a second voltage regulator and a fourth resistor.</p> |