JPH02138920U - - Google Patents
Info
- Publication number
- JPH02138920U JPH02138920U JP4849489U JP4849489U JPH02138920U JP H02138920 U JPH02138920 U JP H02138920U JP 4849489 U JP4849489 U JP 4849489U JP 4849489 U JP4849489 U JP 4849489U JP H02138920 U JPH02138920 U JP H02138920U
- Authority
- JP
- Japan
- Prior art keywords
- frequency synthesizer
- phase
- locked loop
- capacitor
- filter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003990 capacitor Substances 0.000 claims description 4
- 230000001419 dependent effect Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 6
- 230000010355 oscillation Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
Landscapes
- Filters And Equalizers (AREA)
- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
- Superheterodyne Receivers (AREA)
Description
第1図はこの考案の一実施例による周波数シン
セサイザに適用されるLPF6の構成を示す回路
図、第2図は第1図の動作を説明するための図、
第3図はこの考案の一実施例および従来例による
周波数シンセサイザの構成を示すブロツク図、第
4図は従来のLPF6の構成例を示す回路図、第
5図は大容量コンデンサの容量変化率の温度特性
の一例を示す図、第6図は従来のLPF6の減衰
特性の一例を示す図、第7図は従来の周波数シン
セサイザから出力される局部発振信号のスペクト
ラムの一例を示す図である。
9……ラグフイルタ、11……容量付加回路、
12……トランジスタ、13……補正用コンデン
サ、17……サーミスタ。
FIG. 1 is a circuit diagram showing the configuration of an LPF 6 applied to a frequency synthesizer according to an embodiment of this invention, and FIG. 2 is a diagram for explaining the operation of FIG. 1.
Fig. 3 is a block diagram showing the configuration of a frequency synthesizer according to an embodiment of this invention and a conventional example, Fig. 4 is a circuit diagram showing an example of the structure of a conventional LPF6, and Fig. 5 shows the rate of change in capacitance of a large capacitor. FIG. 6 is a diagram showing an example of the attenuation characteristic of a conventional LPF 6, and FIG. 7 is a diagram showing an example of the spectrum of a local oscillation signal output from a conventional frequency synthesizer. 9...Lag filter, 11...Capacitance addition circuit,
12...Transistor, 13...Correction capacitor, 17...Thermistor.
Claims (1)
ロツクドループを構成するループフイルタにラグ
フイルタを具備した周波数シンセサイザにおいて
、補正用コンデンサとスイツチ用トランジスタと
を直列接続した容量付加回路を前記ラグフイルタ
を構成するコンデンサに並列接続し、前記トラン
ジスタの制御端に加えるバイアス電圧を温度依存
素子によつて制御することを特徴とする周波数シ
ンセサイザ。 In a frequency synthesizer that uses a phase-locked loop and has a lag filter in the loop filter that makes up the phase-locked loop, a capacitance addition circuit that includes a correction capacitor and a switching transistor connected in series is connected in parallel to the capacitor that makes up the lag filter. A frequency synthesizer, wherein a bias voltage applied to a control terminal of the transistor is controlled by a temperature dependent element.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4849489U JPH02138920U (en) | 1989-04-25 | 1989-04-25 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4849489U JPH02138920U (en) | 1989-04-25 | 1989-04-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH02138920U true JPH02138920U (en) | 1990-11-20 |
Family
ID=31565349
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP4849489U Pending JPH02138920U (en) | 1989-04-25 | 1989-04-25 |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH02138920U (en) |
-
1989
- 1989-04-25 JP JP4849489U patent/JPH02138920U/ja active Pending
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JPH02138920U (en) | ||
JPS62181017U (en) | ||
JPH0628834Y2 (en) | Frequency synthesizer | |
JPH0434027U (en) | ||
JPH0412708U (en) | ||
JPS6188333U (en) | ||
JPS62161411U (en) | ||
JPS6031303Y2 (en) | tuned circuit | |
JPS6211081Y2 (en) | ||
JPS6178439U (en) | ||
JPS6019239U (en) | oscillation circuit | |
JPH0366223U (en) | ||
JPH03105018U (en) | ||
JPH0295944U (en) | ||
JPH0232239U (en) | ||
JPS6242339U (en) | ||
JPH01124724U (en) | ||
JPH03101046U (en) | ||
JPS63159915U (en) | ||
JPH03107828U (en) | ||
JPH0344911U (en) | ||
JPS61163439U (en) | ||
JPS61104620U (en) | ||
JPS59154927U (en) | Active low pass filter | |
JPS6193014U (en) |