McDermott Will & Emery LLP
MOS varactor and voltage-controlled oscillator using the same
To provide a MOS varactor in which oscillation frequency variation is small and variation in a capacitance changing voltage is small, and a voltage-controlled oscillator using the MOS varactor, as a load capacitor of an oscillating circuit composed of a feedback resistor 1, an amplifier 2, and a crystal vibrator 3, a variable electrostatic capacitor, which is generated between drain/source terminals and a gate terminal of each of MOS transistors 5a and 6a each of which source and drain terminals are short-circuited, is connected. A bulk terminal of each of the MOS transistors 5a and 6a is connected to one terminal of a resistor 19, a voltage is applied to the other terminal of the resistor 19, the bulk terminal of each of the MOS transistors 5a and 6a is connected to one terminal of a capacitor 20, and the other terminal of the capacitor 20 is grounded.
Matsushita Electric Industrial Co., Ltd.
H
H03B
inventional
Hisato Shigeo Takashi Yuichi
Takeuchi Masai Otsuka Tateyama