| 摘要 |
PURPOSE:To decrease the occupied area of capacitors in a chip by adding transistors (TRs) of Darlington connection so as to decrease the capacitance. CONSTITUTION:A TR QD for base current supply is added to a conventional circuit, its collector is connected to a power supply Vcc, the emitter is connected to a capacitor C and the base is connected to an emitter of a TR QB at the off-buffer stage. In employing Darlington connection to the TRs QB, QD, the emitter current of the TR QB is multiplied by hFE of the TR QD and the result is fed to the capacitor C. Since the capacitor C is charged up by using a current being a multiple of hFE to the base current of the TR QD, the circuit level is raised rapidly and the sufficient effect is obtained with a smaller capacitance than that of a conventional circuit. |
