| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a differential amplifier circuit, an output stage circuit and a voltage controlled oscillation circuit, which operate with a low power supply voltage and are hardly affected by a power supply noise. SOLUTION: At least three stages of differential amplifier circuits to operate at the low power supply voltage are connected in the form of ring, and each of differential amplifier circuits is provided with a differential transistor grounding a source electrode, two load circuits respectively connected to the differential transistor and a transistor for bias for respectively impressing a bias voltage to the differential transistor and the respective load circuits. Then, one load circuit is composed of a diode-connected transistor and the other load circuit is connected to an output terminal, where a gate electrode and a drain electrode have mutually opposite polarities. Thus, a positive feedback circuit has a transistor to operate as a negative resistor and the gate electrode of the transistor for bias is connected to a control terminal.</p> |
