Title:
OSCILLATION CIRCUIT AND TUNER CIRCUIT USING THE SAME
Document Type and Number:
Japanese Patent JPH1168458
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To improve characteristics of a mixer by supplying a prescribed first operation current to an oscillation circuit from a first current source at the time of oscillation, supplying a second operation current to the circuit from a second current source in addition to the first operation current by a first current source only at the time of a prescribed frequency band and driving the circuit, thereby optimizing oscillation power. SOLUTION: At the time of Lch reception, an H-bias SN is applied only to the base of the current source transistor Q135 of he current source transistors Q131 and Q134 of oscillating transistors Q131 and Q134 and a second signal SH is not applied to the base of a transistor Q127. As the result of this, only a current 11 becomes an oscillation operation current. As the result of this, linked with the applying of +B power source to the H-band terminal BH of a resonance circuit 20, a prescribed bias SH is applied to the base of Q137 constituting the second transistor of the current source transistor of the oscillating operation transistor. Thus, a current 12 flows through an operating circuit.
Inventors:
YAMADA TSUTOMU
Application Number:
JP22165297A
Publication Date:
March 09, 1999
Filing Date:
August 18, 1997
Export Citation:
Assignee:
SONY CORP
International Classes:
H03B5/12; H03J5/02; H04B1/26; (IPC1-7): H03B5/12; H03J5/02; H04B1/26
Attorney, Agent or Firm:
Takahisa Sato