POWER SUPPLY CIRCUIT
FIG6 is a diagram for illustrating surge protection in the power supply circuit shown in FIG1
FIG6 is a diagram for illustrating surge protection in power supply circuit 10 shown in FIG1. In surge protection circuit 11, capacitor C2 and resistance R1 are connected in series to Zener diode ZD1. The operating voltage (Zener voltage Vz) of Zener diode ZD1 is assumed to be 150 V.
diagram
10
power supply circuit
20
AC power supply
['1. A power supply circuit (10) comprising: a coil (L1) having a first end that receives an input voltage and a second end; a switching element (TR1) connected to the second end of the coil (L1); a first capacitor (C1) connected to the second end of the coil (L1); and a surge protection circuit (11) connected to the second end of the coil (L1) in parallel with the first capacitor (C1), the surge protection circuit (11) including a diode, a second capacitor (C2), and a resistance (R1), the diode, the second capacitor (C2), and the resistance (R1) being connected in series to the second end of the coil (L1).']