| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To making the frequency of an oscillating frequency high, even under a voltage reduction tendency of a logic circuit to be used for a PLL (Phase Locked Loop) circuit while reducing a tolerance of the oscillating frequency in a resonance circuit. <P>SOLUTION: In an LC tuning type voltage controlled oscillator for variably controlling an oscillating frequency, on an emitter side of an oscillation transistor 1, two short stubs P1 and P2 comprising microstrip lines of the same line length are formed between a pair of through-holes H1 and H2 which become a ground potential, and an emitter of the transistor 1 is connected between the short stubs P1 and P2. Namely, the short stubs P1 and P2 are connected in parallel at a position where they become symmetric around an emitter connecting point. Furthermore, a control voltage Vt of 0 to 5 V is applied to a cathode of a varactor Cv DC-cut by capacitors C1 and C2, and a reference voltage, for example, the reference voltage of -5V is applied from a reference voltage source 6 to an anode. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
