JPS6218088B2 - - Google Patents
Info
- Publication number
- JPS6218088B2 JPS6218088B2 JP55164441A JP16444180A JPS6218088B2 JP S6218088 B2 JPS6218088 B2 JP S6218088B2 JP 55164441 A JP55164441 A JP 55164441A JP 16444180 A JP16444180 A JP 16444180A JP S6218088 B2 JPS6218088 B2 JP S6218088B2
- Authority
- JP
- Japan
- Prior art keywords
- resistor
- amplifier
- capacitor
- circuit
- input terminal
- 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.)
- Expired
Links
- 239000003990 capacitor Substances 0.000 claims description 20
- 238000010586 diagram Methods 0.000 description 5
- NAWXUBYGYWOOIX-SFHVURJKSA-N (2s)-2-[[4-[2-(2,4-diaminoquinazolin-6-yl)ethyl]benzoyl]amino]-4-methylidenepentanedioic acid Chemical compound C1=CC2=NC(N)=NC(N)=C2C=C1CCC1=CC=C(C(=O)N[C@@H](CC(=C)C(O)=O)C(O)=O)C=C1 NAWXUBYGYWOOIX-SFHVURJKSA-N 0.000 description 1
- 238000013024 troubleshooting Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H11/00—Networks using active elements
- H03H11/02—Multiple-port networks
- H03H11/04—Frequency selective two-port networks
- H03H11/12—Frequency selective two-port networks using amplifiers with feedback
- H03H11/126—Frequency selective two-port networks using amplifiers with feedback using a single operational amplifier
Description
【発明の詳細な説明】
本発明は、増幅回路に係り、小容量コンデンサ
を用いて高域フイルタを実現し、音質がすぐれ部
品数が少なく経済的である増幅回路を提供するこ
とを目的とする。[Detailed Description of the Invention] The present invention relates to an amplifier circuit, and an object of the present invention is to provide an economical amplifier circuit that realizes a high-frequency filter using a small-capacity capacitor, has excellent sound quality, and has a small number of components. .
一般に、高域フイルタとしては、第１図に示さ
れるような構成の回路がある。この回路において
は、抵抗R1，R2、増幅器１によつて反転型増幅
器を構成し、点線に示す抵抗R3コンデンサC3
サーボアンプ２によつてミラー積分器を構成する
ことで低周波利得を減少していた。この回路によ
ればサーボアンプ２を必要とするが、サーボアン
プは能動素子を用い一般に高価であり、第１図の
回路は不経済であつた。 Generally, as a high-pass filter, there is a circuit having a configuration as shown in FIG. In this circuit, resistors R 1 , R 2 and amplifier 1 constitute an inverting amplifier, with resistor R 3 capacitor C 3 shown as a dotted line.
The servo amplifier 2 forms a Miller integrator to reduce the low frequency gain. This circuit requires a servo amplifier 2, but servo amplifiers use active elements and are generally expensive, making the circuit of FIG. 1 uneconomical.
上記欠点をなくすために、従来、第２図に示さ
れるような構成の回路がある。この回路において
は、抵抗R3，R4増幅器１よりなる反転型増幅器
の出力にコンデンサC2抵抗R5からなる高域フイ
ルタ回路を接続することにより、入出力間で所定
の高域フイルタ特性を得ていた。ところが、この
回路では出力信号が直接コンデンサC2を通過す
るために、コンデンサC2が音質等に与える影響
は大きく、オーデイオ用増幅器としては望ましい
ものではない。又、抵抗R5の値によつては、コ
ンデンサC2は大容量となり、一般に大容量のコ
ンデンサは、特性、音質的にも問題が多い等の欠
点があつた。 In order to eliminate the above-mentioned drawbacks, there has conventionally been a circuit having a configuration as shown in FIG. In this circuit, by connecting a high-pass filter circuit consisting of a capacitor C and a resistor R5 to the output of an inverting amplifier consisting of an amplifier 1 consisting of resistors R 3 and R 4 , a predetermined high-pass filter characteristic is established between the input and output. I was getting it. However, in this circuit, since the output signal passes directly through capacitor C2 , capacitor C2 has a large effect on sound quality, etc., and is not desirable as an audio amplifier. Furthermore, depending on the value of the resistor R5 , the capacitor C2 has a large capacity, and generally large capacitors have drawbacks such as having many problems in terms of characteristics and sound quality.
本発明は、上記欠点を除去するものであり、第
３図以下と共にその１実施例につき説明する。増
幅器１の反転入力端子と出力端子４とを抵抗R8
で接続し、同反転入力端子と抵抗R6，R7からな
る帰還回路とをコンデンサC3で接続したことに
よつて構成されている。このように構成された回
路において、入力端子３の電圧をｅi、抵抗R6の
後の電圧をｅi′、出力端子電圧をe0、抵抗R7に流
れる電流をi1、抵抗R8に流れる電流をi2とする。
又、増幅器１の利得は十分に大きいので、反転入
力端子はイマジナリーアースが成立するものとす
ると、即ち反転入力端子へは、電流は流れこまな
いとすると、下記の式が成立する。 The present invention eliminates the above-mentioned drawbacks, and one embodiment thereof will be described with reference to FIG. 3 and the following figures. Connect the inverting input terminal of amplifier 1 and output terminal 4 with resistor R 8
The inverting input terminal and a feedback circuit consisting of resistors R 6 and R 7 are connected by a capacitor C 3 . In the circuit configured in this way, the voltage at the input terminal 3 is e i , the voltage after the resistor R 6 is e i ', the output terminal voltage is e 0 , the current flowing through the resistor R 7 is i 1 , and the resistor R 8 is Let the current flowing through i2 be i2.
Further, since the gain of the amplifier 1 is sufficiently large, it is assumed that an imaginary earth is established at the inverting input terminal, that is, assuming that no current flows into the inverting input terminal, the following equation is established.
i1＋i2＝（ｅi―ｅi′）１／R6 ……(1)
i2＝（Ｏ―e0）１／R8 ……(2)
i1＝（ｅi′―e0）１／R7 ……(3)
i2＝SC3ei′ ……(4)
上記(1)、(2)、(3)、(4)式を整理して、入出力特性
を求めると下記のようになる。i 1 + i 2 = (e i - e i ′) 1/R 6 ...(1) i 2 = (O-e 0 ) 1/R 8 ......(2) i 1 = (e i ′-e 0 )1/R 7 ...(3) i 2 =SC 3 e i ′ ...(4) Arrange the above equations (1), (2), (3), and (4) to find the input-output characteristics. and as below.
上式(5)の周波数利得特性は、第４図のようにな
り、高域での安定した領域での利得は、
Ｒ７Ｒ８／Ｒ６（Ｒ７＋Ｒ８）となり、高域フイルタ周
波数f1は、
Ｒ６＋Ｒ７／２πＣ３Ｒ６（Ｒ７＋Ｒ８）となり、抵抗
R8を抵抗R6，R7に
比べて十分大きくとれば、この周波数f1は、コン
デンサC3と抵抗R6，R7，R8によつて決定される
が抵抗R8を高抵抗にすれば、同一のカツトオフ
周波数であればコンデンサC3は、小容量のもの
が使えることになる。コンデンサC3が小容量の
ものであればコストを安くでき、かつ音質面です
ぐれたコンデンサが使用できるという利点があ
る。又、増幅器１をDCドリフト特性に留意した
設計にすれば、出力端子４のDCドリフト特性は
増幅器１の入力換算DCドリフト特性が現われて
くるので、第１図のようにDCサーボ回路を付加
したのと同じ効果が得られる。 The frequency gain characteristic of the above formula (5) is as shown in Figure 4, and the gain in the stable high frequency region is:
R 7 R 8 /R 6 (R 7 +R 8 ), and the high-pass filter frequency f 1 is R 6 +R 7 /2πC 3 R 6 (R 7 +R 8 ), and the resistance
If R 8 is set sufficiently large compared to resistors R 6 and R 7 , this frequency f 1 is determined by capacitor C 3 and resistors R 6 , R 7 , and R 8 , but resistor R 8 is set to a high resistance. Then, if the cutoff frequency is the same, a small capacitance capacitor C3 can be used. If the capacitor C3 has a small capacity, the cost can be reduced and a capacitor with excellent sound quality can be used. Also, if amplifier 1 is designed with DC drift characteristics in mind, the DC drift characteristics of output terminal 4 will reflect the input converted DC drift characteristics of amplifier 1, so a DC servo circuit is added as shown in Figure 1. You can get the same effect as .
又、第５図のように、入力信号源が高い出力イ
ンピーダンスを持つ電流源とみなせる場合におい
ても、前記第２図の場合と同様の考え方ができ
る。第４図において、次式が成立する。 Furthermore, even when the input signal source can be regarded as a current source with high output impedance, as shown in FIG. 5, the same concept as in the case of FIG. 2 can be used. In FIG. 4, the following equation holds.
i3＝i1＋i2 ……(6)
i1＝（ｅi―e0）１／R9 ……(7)
i2＝（Ｏ―e0）１／R10 ……(8)
i2＝（ｅi―ｏ）SC4 ……(9)
上記(6)、(7)、(8)、(9)式を整理して、入出力特性
を求めると下記のようになる。i 3 = i 1 + i 2 ...(6) i 1 = (e i - e 0 ) 1/R 9 ... (7) i 2 = (O - e 0 ) 1/R 10 ... (8) i 2 = (e i −o) SC 4 ...(9) By rearranging the above equations (6), (7), (8), and (9), the input/output characteristics are determined as follows.
上式(10)の周波数利得特性は、第６図のようにな
り、高域での安定した領域での利得は、Ｒ９Ｒ１０／Ｒ
９＋Ｒ１０
となり、高域フイルタ周波数f1は１／２πＣ４（Ｒ９＋
Ｒ１０）
となり、抵抗R10を抵抗R9に比べて十分大きくと
れば、この周波数f1はほぼコンデンサC4と抵抗
R10によつて決定される。よつてこの場合も、第
２図の場合と同様にコンデンサC4を小容量に選
択できる。 The frequency gain characteristic of the above formula (10) is as shown in Fig. 6, and the gain in the stable high frequency region is R 9 R 10 /R
9 +R 10 , and the high-pass filter frequency f 1 is 1/2πC 4 (R 9 +
R10 ), and if the resistor R10 is made sufficiently larger than the resistor R9 , this frequency f1 will be approximately the same as the capacitor C4 and the resistor.
Determined by R 10 . Therefore, in this case, as in the case of FIG. 2, the capacitor C4 can be selected to have a small capacity.
上述の如く、本発明になる増幅回路は、反転増
幅器の反転入力端子と出力端子との間を第１の抵
抗で接続し、前記反転入力端子とこの第１の抵抗
との接続点にコンデンサの一端を接続してその他
端をこの回路の信号入力端子に接続すると共に第
２の抵抗を介して上記出力端子に接続し、上記第
１及び第２の抵抗及び上記コンデンサにて高域フ
イルタ特性を有する構成としたため、小容量コン
デンサを使用でき、部品数が少なく経済的であ
り、故障修理も容易で、音質特性のすぐれた増幅
回路が得られる等の効果が得られる。 As described above, the amplifier circuit according to the present invention connects the inverting input terminal and the output terminal of the inverting amplifier with a first resistor, and connects a capacitor to the connection point between the inverting input terminal and the first resistor. One end is connected and the other end is connected to the signal input terminal of this circuit and also connected to the above output terminal via a second resistor, and the high frequency filter characteristics are controlled by the above first and second resistors and the above capacitor. Because of this structure, a small capacitor can be used, the number of parts is small, it is economical, and troubleshooting is easy, and an amplifier circuit with excellent sound quality characteristics can be obtained.
第１図及び第２図は従来の増幅回路の回路図、
第３図は本発明になる増幅回路の一実施例の回路
図、第４図は第３図の回路の周波数利得特性図、
第５図は第３図の増幅回路に電流源を接続した
図、第６図は第５図の回路の周波数利得特性図で
ある。
１…増幅器、２…サーボアンプ、３…入力端
子、４…出力端子、R1〜R10…抵抗、C1〜C4…コ
ンデンサ、i1，i2…電流、i3…電流源、ｅi…入力
電圧、e0…出力電圧。
Figures 1 and 2 are circuit diagrams of conventional amplifier circuits,
FIG. 3 is a circuit diagram of an embodiment of the amplifier circuit according to the present invention, FIG. 4 is a frequency gain characteristic diagram of the circuit of FIG. 3,
FIG. 5 is a diagram in which a current source is connected to the amplifier circuit in FIG. 3, and FIG. 6 is a frequency gain characteristic diagram of the circuit in FIG. 1...Amplifier, 2...Servo amplifier, 3...Input terminal, 4...Output terminal, R1 to R10 ...Resistor, C1 to C4 ...Capacitor, i1 , i2 ...Current, i3 ...Current source, e i ...input voltage, e 0 ...output voltage.
Claims (1)
を第１の抵抗で接続し、前記反転入力端子と該第
１の抵抗との接続点にコンデンサの一端を接続し
てその他端をこの回路の信号入力端子に接続する
と共に第２の抵抗を介して上記出力端子に接続
し、上記第１及び第２の抵抗及び上記コンデンサ
にて高域フイルタ特性を有するよう構成したこと
を特徴とする増幅回路。1 Connect the inverting input terminal and output terminal of the inverting amplifier with a first resistor, connect one end of the capacitor to the connection point between the inverting input terminal and the first resistor, and connect the other end to the connection point of the inverting input terminal and the first resistor. An amplifier circuit connected to a signal input terminal and connected to the output terminal via a second resistor, and configured to have high-pass filter characteristics with the first and second resistors and the capacitor. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55164441A JPS5787616A (en) | 1980-11-21 | 1980-11-21 | Amplifying circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55164441A JPS5787616A (en) | 1980-11-21 | 1980-11-21 | Amplifying circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5787616A JPS5787616A (en) | 1982-06-01 |
| JPS6218088B2 true JPS6218088B2 (en) | 1987-04-21 |
Family
ID=15793217
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55164441A Granted JPS5787616A (en) | 1980-11-21 | 1980-11-21 | Amplifying circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5787616A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59133745A (en) * | 1983-01-20 | 1984-08-01 | Matsushita Electric Ind Co Ltd | Optical receiving circuit |
| JP2008219699A (en) * | 2007-03-07 | 2008-09-18 | Hitachi Metals Ltd | Low-noise amplifier circuit, high-frequency circuit, high-frequency component, and communication device |
-
1980
- 1980-11-21 JP JP55164441A patent/JPS5787616A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5787616A (en) | 1982-06-01 |
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