| 摘要 |
PURPOSE:To simplify the entire constitution by selecting a capacitance in an SCF and using a part of capacitor and a switch circuit in common. CONSTITUTION:With Ps='0', a capacitor K1C1 is charged by an input voltage Vin, and with Ps='1', the charging voltage is fed inversly to an amplifier 21, a circuit 31 is equivalent to a circuit 11. With Ps='1', the capacitor K1C1 is charged by an output voltage Vout and fed to the amplifier 21, then the circuit 31 is equivalent to a circuit 13 with the condition of K3=K1. Thus, the circuit 31 is equivalent to the circuits 11, 13 with K1=K2. With the similar reason, the circuit 32 is equivalent to the circuits 12, 14 with K2=K4. Thus, the circuit acts like a low pass filter. |
