JPH01127019U - - Google Patents
Info
- Publication number
- JPH01127019U JPH01127019U JP2451788U JP2451788U JPH01127019U JP H01127019 U JPH01127019 U JP H01127019U JP 2451788 U JP2451788 U JP 2451788U JP 2451788 U JP2451788 U JP 2451788U JP H01127019 U JPH01127019 U JP H01127019U
- Authority
- JP
- Japan
- Prior art keywords
- output signal
- circuit
- oscillation circuit
- level
- noise removal
- 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.)
- Granted
Links
- 230000010355 oscillation Effects 0.000 claims description 7
- 238000010586 diagram Methods 0.000 description 5
Description
第１図は本考案の第１の実施例のブロツク図、
第２図は第１図に示された実施例の雑音除去回路
の一例を示す回路図、第３図は本考案の第２の実
施例のブロツク図、第４図は従来のクロツク発生
回路の一例を示すブロツク図である。
１Ａ，１Ｂ……発振回路、２……雑音除去回路
、３……選択回路、４……分周回路、１０Ａ，１
０Ｂ……発振子、２１……シフトレジスタ、２２
……ＲＳフリツプフロツプ、ＦＦ１〜ＦＦ３……
フリツプフロツプ、Ｇ１……ＮＯＲゲート、Ｇ２
……ＡＮＤゲート、１……インバータ。
FIG. 1 is a block diagram of the first embodiment of the present invention.
2 is a circuit diagram showing an example of the noise removal circuit of the embodiment shown in FIG. 1, FIG. 3 is a block diagram of the second embodiment of the present invention, and FIG. 4 is a circuit diagram of a conventional clock generation circuit. FIG. 2 is a block diagram showing an example. 1A, 1B...Oscillation circuit, 2...Noise removal circuit, 3...Selection circuit, 4...Frequency division circuit, 10A, 1
0B...Resonator, 21...Shift register, 22
...RS flip-flop, FF 1 ~ FF 3 ...
Flip-flop, G1 ...NOR gate, G2
...AND gate, 1 ...inverter.
Claims (1)
の第１の発振回路より十分高い周波数で発振する
第２の発振回路と、この第２の発振回路の出力信
号により前記第１の発振回路の出力信号を所定の
周期でサンプリングし、このサンプリングした隣
接する複数の信号のレベルが、共に第１のレベル
になつたとき出力信号を第１のレベルにセツトし
、共に第２のレベルになつたとき出力信号を第２
のレベルにセツトする雑音除去回路と、選択信号
により前記雑音除去回路の出力信号と前記第２の
発振回路の出力信号とを切換えて出力する選択回
路とを有することを特徴とするクロツク発生回路
。 A first oscillation circuit that oscillates at a predetermined frequency, a second oscillation circuit that oscillates at a sufficiently higher frequency than the first oscillation circuit, and an output signal of the second oscillation circuit that causes the first oscillation circuit to oscillate. The output signal is sampled at a predetermined period, and when the levels of a plurality of sampled adjacent signals both reach the first level, the output signal is set to the first level, and the output signal is set to the second level. When the output signal is the second
1. A clock generation circuit comprising: a noise removal circuit that sets the output signal to the level of the noise removal circuit; and a selection circuit that selects and outputs the output signal of the noise removal circuit and the output signal of the second oscillation circuit according to a selection signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2451788U JPH067383Y2 (en) | 1988-02-25 | 1988-02-25 | Clock generator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2451788U JPH067383Y2 (en) | 1988-02-25 | 1988-02-25 | Clock generator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01127019U true JPH01127019U (en) | 1989-08-30 |
| JPH067383Y2 JPH067383Y2 (en) | 1994-02-23 |
Family
ID=31244430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2451788U Expired - Lifetime JPH067383Y2 (en) | 1988-02-25 | 1988-02-25 | Clock generator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH067383Y2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0553677A (en) * | 1991-08-26 | 1993-03-05 | Nec Corp | Oscillation circuit |
-
1988
- 1988-02-25 JP JP2451788U patent/JPH067383Y2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0553677A (en) * | 1991-08-26 | 1993-03-05 | Nec Corp | Oscillation circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH067383Y2 (en) | 1994-02-23 |