| 摘要 |
<p>Even if there are variations between internal resistors of smoothing capacitors, to prevent with a simple configuration a voltage greater than the rated voltage of a smoothing capacitor from being applied to that capacitor. And to maintain with a simple configuration a balance between voltages applied to smoothing capacitors. A voltage smoothing circuit (14) is equipped with a first smoothing capacitor (C1), a second smoothing capacitor (C2), a balancing resistor (R3), and a Zener diode (RZ4). The first smoothing capacitor (C1) and the second smoothing capacitor (C2) are connected in series to each other and are connected in parallel to a power supply portion (13). The balancing resistor (R3) is connected in parallel to the first smoothing capacitor (C1). The Zener diode (RZ4) is connected on a current path (14) in parallel with the second smoothing capacitor (C2). The Zener diode (RZ4) conducts current in one direction on the current path (14) in a case where a voltage equal to or greater than a Zener voltage (Vr4) has been applied.</p> |
