| 摘要 |
PURPOSE:To make power consumption low by driving the constant-current source in the amplification stage by the consumption current of a frequency divider circuit in the oscillator circuit using FETs. CONSTITUTION:The get bias of FET 3 which constitutes a constant-current source by utilizing a frequency division current flowing to a frequency divider circuit cascaded to an oscillator circuit is determined. Since FET 3 and FET 4 are formed on the same chip and have approximately equal threshold voltages, FET 3 operates always in a saturation state and becomes a constant-current source if the gate voltage is fixed. The gate voltage is fixed in respect to time by the action of capacitor 5. Unstability of oscillation and frequency division at a power supply time is resolved by a power on reset circuit which turns on the constant-current circuit simultaneously with resetting the frequency divider circuit at a power suply time. |
