| 摘要 |
<p>An oscillator which is used for a portable telephone or the like, comprises a transistor fabricated by MOS process, and entails a low level of noise other than the desired oscillation frequency. The oscillator includes quartz oscillating element (1) and a first amplifier (3) connected between input and output terminals (4, 2). The first amplifier (3) has a first P-type transistor (11) and a first N-type transistor (12) both fabricated by MOS process. A gate (23) of the first P-type transistor (11) spans between a P-type source diffused region (22) and a P-type drain diffused region (21). A gate of the first N-type transistor (12) spans between an N-type source diffused region (18) and an N-type drain diffused region (19). The span of the gate (20) of the first N-type transistor (12) is longer than that of the gate (23), and the field strength is low, thereby lowering the noise level other than the oscillation frequency.</p> |
