JP2004119885A - Optical receiver and peak sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical receiver and a peak sensor which improves its receiving performance by suppressing the accompanied peaking of its receiving gain by the inductance quality of its bonding wire. <P>SOLUTION: A peaking adjusting portion 41 has a resistor R1 whereby a photodiode PD and its power-supply feeding line are connected in series with each other and a capacitor C1 whereby the power-supply feeding line and a grounded potential present inside an integrated circuit are connected. The peaking adjusting portion 41 is provided between the photodiode PD and its power-supply feeding line. Then, by setting the resistor R1 to an appropriate value, a finite value is so given to a Zin of the optical receiver even while a Cpd and an Lw are resonant with each other as to suppress the change of a gain value Zt of the optical receiver. Thereby, the occurrence of the peaking of the optical receiver is prevented. <P>COPYRIGHT: (C)2004,JPO

Description

【０００７】
ここで、Ｓ１１、Ｓ２１はそれぞれＳパラメタの入力反射成分と入力信号通過成分を示し、Ｚｏは系のインピーダンスを示す。式（１）から明らかなように、利得Ｚｔは入力反射成分であるＳ１１の値により大きく変動する。すなわち、Ｓ１１が１に近づくにつれＺｔが無限大へ増大する。一方、ボンディングワイヤのインダクタンス成分によるインピーダンスは周波数とともに増大する。このことが入力反射成分Ｓ１１の値を１に近づける作用を及ぼし、結果として受信利得は高周波領域にピークを示す。これが、いわゆるピーキングと呼ばれる現象である。
【０００８】
ピーキングが生じると、ある特定周波数の利得が増大し利得偏差が生じる。その結果として受信信号にリンギングなどが重畳され、受信信号の波形が劣化する。このような事態に陥るとビットエラー率が増加するなどの悪影響が生じ、通信システムの性能に害を及ぼす。
【０００９】
なお、光通信システムにおける受信帯域の拡大に関する技術を開示した公知文献として、下記の特許文献１がある。この文献には、ボンディングワイヤの長さを極力短くすることでインダクタンス成分を抑圧できることが述べられている。また、光／電気変換素子の信号側ラインのみならず電源側ラインについてもその長さを十分に短くできるようにし、ＧＨｚ帯のような広帯域光信号を良好に受信できるようにした発明が開示されている。
【００１０】
しかしながら近年においては、通信システムにおける帯域需要はますます大きくなってきており、受信装置において求められる性能も厳しさを増しているため、現時点では下記特許文献が出願された時点におけるよりもさらに高度な性能が求められている。
【００１１】
【特許文献１】
特開２０００−２６９５４１号公報（段落番号［０００６］、［００１３］）
【００１２】
【発明が解決しようとする課題】
上記したように、ＰＩＮ型フォトダイオードと電気信号増幅器とは、光受信装置への実装にあたり互いにボンディングワイヤを介して接続される。ボンディングワイヤのインダクタンス成分によるインピーダンスは高周波領域において顕著となるため、特に広帯域信号を受信する際にはピーキングを生じて信号波形が劣化するという不具合がある。
【００１３】
本発明は上記事情によりなされたもので、その目的は、ボンディングワイヤのインダクタンス性に伴う受信利得のピーキングを抑圧し、これにより受信性能の向上を図った光受信装置およびピーク検出器を提供することにある。
【００１４】
【課題を解決するための手段】
上記目的を達成するために本発明は、光信号を光／電気変換素子により電気信号に変換し、この電気信号を集積回路内に入力して該集積回路内の増幅器により増幅する光受信装置において、前記光／電気変換素子に前記集積回路の内部を通して電源電流を供給する電源供給手段と、所定のインダクタンス成分を有し前記光／電気変換素子の電源側端子を前記集積回路に接続する接続手段（例えばボンディングワイヤなど）と、前記電源供給手段と前記電源側端子との間に設けられ、前記インダクタンス成分に基づく前記電気信号のピーキングを制御するピーキング制御手段とを具備することを特徴とする。
【００１５】
ピーキング制御手段は、例えば前記光／電気変換素子の電源側端子と前記電源供給手段との接続経路中に直列に設けられる抵抗素子と、この抵抗素子と前記集積回路の内部接地電位との間に並列に設けられるキャパシタ素子とを備え手構成される。
【００１６】
このような構成とすると、光／電気変換素子の寄生容量Ｃｐｄとボンディングワイヤのインダクタンス成分Ｌｗとが共振状態にある場合でも、抵抗素子およびキャパシタ素子により光／電気変換素子から増幅器への入力インピーダンスＺｉｎを有限な値に保つことができるようになる。従ってボンディングワイヤのインダクタンス性により生じるピーキングを抑圧することができ、利得偏差の少ない良好な周波数特性が得られる。
【００１７】
【発明の実施の形態】
以下、図面を参照して本発明の実施の形態を詳細に説明する。
【００１８】
（第１の実施形態）
図１は本発明に係わる光受信装置の第１の実施の形態を示す機能ブロック図である。図１において、光信号入力部１を介して導入された光信号は光／電気変換素子２により電気信号に変換される。この電気信号は増幅器５により所定の利得で増幅されて電気信号出力部６から出力される。
【００１９】
光／電気変換素子２は電源電圧供給部３から駆動電圧の供給を受けて動作する。本実施形態では光／電気変換素子２と電源電圧供給部３との間にピーキング調整部４１を設ける。増幅器５とピーキング調整部４１はともに集積化され、共通の集積回路内に設けられる。
【００２０】
図２は、図１に示される光受信装置の一実施の形態を示す回路図である。図２におけるフォトダイオード（ＰＤ）が図１の光／電気変換素子２に対応する。好ましくは、フォトダイオードＰＤとしてＰＩＮ型フォトダイオードを用いると良い。このフォトダイオードＰＤは、等価回路におけるキャパシタＣｐｄとして表される寄生容量を有する。また増幅器５としては、トランスインピーダンスアンプなどを用いるのが好ましい。フォトダイオードＰＤはボンディングワイヤを介して増幅器５に接続され、そのインダクタンス成分を等価回路インダクタＬｗとして示す。
【００２１】
ピーキング調整部４１は集積回路内部において、フォトダイオードＰＤとその電源供給ラインとの間に設けられる。ピーキング調整部４１は、フォトダイオードＰＤと電源供給ラインとの間に直列に接続される抵抗Ｒ１、および、電源供給ラインと集積回路内部の接地電位との間に接続されるキャパシタＣ１とを備える。このような構成において、光入力信号はフォトダイオードＰＤにおいて電流信号に変換され、この電流信号は増幅器５へと伝達される。
【００２２】
一般に、この電流信号に含まれる高周波信号（例えばＧＨｚ帯）は、Ｃｐｄ，Ｌｗなどの寄生成分により増幅器５へ伝達されにくくなる。フォトダイオードＰＤの純ダイオード成分から増幅器５への入力インピーダンスＺｉｎを求めると、Ｒ１が０の場合、すなわち従来の光受信装置におけるＺｉｎは、次式（２）で表される。
【００２３】
【数２】

【００２４】
式（２）において、例えばＣｐｄ＝０．３ｐＦ、Ｌｗ＝１ｎＨのとき、およそ９．２ＧＨｚで共振状態となり、Ｚｉｎは無限大となる。よって式（１）から利得Ｚｔも無限大となり、ピーキングが発生する。
【００２５】
一方、本実施形態においては、Ｒ１として或る適切な有限値を選ぶことが可能である。図２の構成においてＺｉｎは次式（３）となる。
【００２６】
【数３】

【００２７】
すなわち、ＣｐｄとＬｗが共振状態でもＺｉｎは有限値を持ち、従って式（１）式から利得Ｚｔの値に大きな変化は生じなくなる。これによりピーキングを抑圧することができ、理想的な出力信号波形を得ることができる。
【００２８】
図３は、本実施形態の光受信装置のトランスインピーダンスアンプの利得の周波数特性を従来と比較して示す図である。図３（１）に示される従来の特性では、１０ＧＨｚ付近に８ｄＢ前後のピーキングが発生している。これに対し本実施形態の光受信装置の特性は、図３（２）に示されるように良好な結果を得られている。
【００２９】
図４は、本実施形態の光受信装置のトランスインピーダンスアンプの群遅延特性を従来と比較して示す図である。図４（１）に示される従来の特性では、ピーキングが生じている１０ＧＨｚ付近で群遅延偏差が急激に増加している。これに対し本実施形態の光受信装置の特性は、図４（２）に示されるように、群遅延偏差が全ての周波数帯域にわたり非常に少ないことがわかる。
【００３０】
このように本実施形態では、フォトダイオードＰＤと電源供給ラインとの間に直列に接続される抵抗器Ｒ１、および、電源供給ラインと集積回路内部の接地電位との間に接続されるキャパシタＣ１とを備えるピーキング調整部４１を、フォトダイオードＰＤとその電源供給ラインとの間にピーキング調整部４１を設ける。そして、抵抗器Ｒ１として適切な値を設定し、ＣｐｄとＬｗが共振状態にある場合でもＺｉｎに有限値をとらせるようにして、利得Ｚｔの値の変化を抑圧する。これによりピーキングの発生を防止するようにしている。
【００３１】
これにより、本実施形態の光受信装置を例えば高速光通信の受信装置に使用した場合でも、フォトダイオードＰＤと増幅器５とをボンディングワイヤを介して接続することにより生じるピーキングを効果的に抑制することができ、波形劣化の無い良好な信号を出力することができる。
【００３２】
（第２の実施形態）
図５は本発明に係わる光受信装置の第２の実施の形態を示す機能ブロック図である。この実施形態は、特性可変型のピーキング調整部４２（図１との区別のため参照符号４２を付す）を設ける。また増幅器５と電気信号出力部６との間にピーク検出器７を設け、ピーク検出器７におけるピーキングの検出結果によりピーキング調整部４２の特性を制御するようにしたものである。
【００３３】
図６は、図５に示される光受信装置の一実施の形態を示す回路図である。図６においてピーキング調整部４２は、それぞれ抵抗値の異なる抵抗器Ｒ１，Ｒ２を備える。これらの抵抗器はピーク検出器７から与えられるピーク検知信号により切り替えられ、ピーキング調整部４２のピーキング抑圧特性を可変する。なお図６においても、フォトダイオードＰＤへの電源供給ラインと集積回路内部の接地電位との間に、キャパシタＣ１を接続してもよい。また、複数の抵抗器を切り替える代わりに、可変抵抗器を用いるようにしても良い。
【００３４】
図７は、図６のピーク検出器７の一構成例を示す回路図である。図７において、増幅器５からの電気出力信号はその一部が分岐され、それぞれ周波数特性の異なる微分回路４２１，４２２に入力される。各微分回路４２１，４２２は電気出力信号の異なる周波数帯における微分値を出力し、減算器４２３に入力する。減算器４２３は各微分値の差を求め、これをピーク検出信号としてピーキング調整部に与える。
【００３５】
このような構成であるから、本実施形態の光受信装置は、如何なる使用状態においてもピーキング抑圧特性を最適な状態に自動的に調整することが可能となる。従ってこの実施形態の光受信装置は、幹線系システムから家庭用の用途に至るまで、幅広く利用することができる。
【００３６】
【発明の効果】
以上詳述したように本発明によれば、ボンディングワイヤのインダクタンス性に伴う受信利得のピーキングを抑圧でき、これにより受信性能の向上を図った光受信装置およびピーク検出器を提供することができる。
【図面の簡単な説明】
【図１】本発明に係わる光受信装置の第１の実施の形態を示す機能ブロック図。
【図２】図１に示される光受信装置の一実施の形態を示す回路図。
【図３】本発明の実施の形態に係わる光受信装置のトランスインピーダンスアンプの利得の周波数特性を従来と比較して示す図。
【図４】本発明の実施の形態に係わる光受信装置のトランスインピーダンスアンプの群遅延特性を従来と比較して示す図。
【図５】本発明に係わる光受信装置の第２の実施の形態を示す機能ブロック図。
【図６】図５に示される光受信装置の一実施の形態を示す回路図。
【図７】図６のピーク検出器７の一構成例を示す回路図。
【符号の説明】
１…光信号入力部
２…光／電気変換素子
３…電源電圧供給部
４１，４２…ピーキング調整部
５…増幅器
６…電気信号出力部
７…ピーク検出器[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical receiving device and a peak detector used in the optical receiving device.
[0002]
[Prior art]
2. Description of the Related Art An optical receiving apparatus generally has a configuration in which incoming light is converted into an electric signal by a photoelectric conversion element, and the obtained electric signal is amplified with a predetermined gain by an amplifier. A PIN photodiode is generally used as the photoelectric conversion element, and a transimpedance amplifier circuit is generally used as the amplifier.
[0003]
It is difficult to form a photoelectric conversion element and an amplifier on the same element substrate in one process. Therefore, a manufacturing process is generally used in which a photoelectric conversion element is used as an element chip and an amplifier is individually manufactured as an integrated circuit, and both are brought close to each other on a substrate and electrically connected to each other via bonding wires.
[0004]
By the way, in recent years, with an increase in transmission rate in an optical communication system, an improvement in reception performance of a broadband signal has been demanded also in an optical receiver. However, when the band extends to the order of several GHz, the length of the bonding wire affects the reception performance. In the high frequency region, the inductance component of the bonding wire becomes dominant, and it becomes difficult for a high frequency signal to pass from the photoelectric conversion element to the amplifier.
[0005]
Among the amplifiers, the gain Zt of the transimpedance amplifier is generally represented by the following equation (1).
[0006]
(Equation 1)

[0007]
Here, S11 and S21 indicate the input reflection component and the input signal passing component of the S parameter, respectively, and Zo indicates the impedance of the system. As is clear from the equation (1), the gain Zt greatly varies depending on the value of S11 which is an input reflection component. That is, as S11 approaches 1, Zt increases to infinity. On the other hand, the impedance due to the inductance component of the bonding wire increases with the frequency. This has the effect of bringing the value of the input reflection component S11 closer to 1, and as a result, the reception gain shows a peak in the high frequency region. This is a phenomenon called so-called peaking.
[0008]
When the peaking occurs, the gain of a specific frequency increases and a gain deviation occurs. As a result, ringing or the like is superimposed on the received signal, and the waveform of the received signal deteriorates. When such a situation occurs, adverse effects such as an increase in the bit error rate occur, which adversely affects the performance of the communication system.
[0009]
As a known document that discloses a technique related to expansion of a reception band in an optical communication system, there is Patent Document 1 below. This document describes that the inductance component can be suppressed by shortening the length of the bonding wire as much as possible. Also disclosed is an invention in which not only the signal-side line but also the power-supply-side line of the optical / electrical conversion element can be made sufficiently short in length so that a wideband optical signal such as a GHz band can be received well. ing.
[0010]
However, in recent years, the bandwidth demand in the communication system has become more and more strict, and the performance required in the receiving apparatus has also been increasing strictly. Performance is required.
[0011]
[Patent Document 1]
JP-A-2000-269541 (paragraph numbers [0006] and [0013])
[0012]
[Problems to be solved by the invention]
As described above, the PIN photodiode and the electric signal amplifier are connected to each other via the bonding wire when mounted on the optical receiver. Since the impedance due to the inductance component of the bonding wire becomes remarkable in a high frequency region, there is a problem that peaking occurs and a signal waveform is deteriorated particularly when a broadband signal is received.
[0013]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical receiver and a peak detector that suppress peaking of a reception gain due to the inductance property of a bonding wire and thereby improve reception performance. It is in.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the present invention relates to an optical receiver for converting an optical signal into an electric signal by an optical / electrical conversion element, inputting the electric signal into an integrated circuit, and amplifying the electric signal by an amplifier in the integrated circuit. Power supply means for supplying a power current to the optical / electrical conversion element through the inside of the integrated circuit; and connecting means having a predetermined inductance component and connecting a power supply side terminal of the optical / electrical conversion element to the integrated circuit. (E.g., a bonding wire) and a peaking control unit provided between the power supply unit and the power supply side terminal and configured to control peaking of the electric signal based on the inductance component.
[0015]
The peaking control means includes, for example, a resistance element provided in series in a connection path between the power supply side terminal of the optical / electrical conversion element and the power supply means, and between the resistance element and an internal ground potential of the integrated circuit. And a capacitor element provided in parallel.
[0016]
With such a configuration, even when the parasitic capacitance Cpd of the optical / electrical conversion element and the inductance component Lw of the bonding wire are in a resonance state, the input impedance Zin from the optical / electrical conversion element to the amplifier by the resistance element and the capacitor element. Can be kept at a finite value. Therefore, peaking caused by the inductance of the bonding wire can be suppressed, and good frequency characteristics with little gain deviation can be obtained.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0018]
(1st Embodiment)
FIG. 1 is a functional block diagram showing a first embodiment of the optical receiver according to the present invention. In FIG. 1, an optical signal introduced via an optical signal input unit 1 is converted into an electric signal by an optical / electrical conversion element 2. This electric signal is amplified by the amplifier 5 with a predetermined gain and output from the electric signal output unit 6.
[0019]
The optical / electrical conversion element 2 operates upon receiving a drive voltage from the power supply voltage supply unit 3. In the present embodiment, a peaking adjusting unit 41 is provided between the optical / electrical conversion element 2 and the power supply unit 3. The amplifier 5 and the peaking adjustment unit 41 are integrated together and provided in a common integrated circuit.
[0020]
FIG. 2 is a circuit diagram showing an embodiment of the optical receiver shown in FIG. The photodiode (PD) in FIG. 2 corresponds to the light / electric conversion element 2 in FIG. Preferably, a PIN photodiode is used as the photodiode PD. This photodiode PD has a parasitic capacitance represented as a capacitor Cpd in an equivalent circuit. As the amplifier 5, it is preferable to use a transimpedance amplifier or the like. The photodiode PD is connected to the amplifier 5 via a bonding wire, and its inductance component is shown as an equivalent circuit inductor Lw.
[0021]
The peaking adjustment unit 41 is provided between the photodiode PD and its power supply line inside the integrated circuit. The peaking adjustment unit 41 includes a resistor R1 connected in series between the photodiode PD and a power supply line, and a capacitor C1 connected between the power supply line and a ground potential inside the integrated circuit. In such a configuration, the optical input signal is converted into a current signal in the photodiode PD, and this current signal is transmitted to the amplifier 5.
[0022]
Generally, a high-frequency signal (for example, a GHz band) included in the current signal is difficult to be transmitted to the amplifier 5 due to parasitic components such as Cpd and Lw. When the input impedance Zin to the amplifier 5 is obtained from the pure diode component of the photodiode PD, when R1 is 0, that is, Zin in the conventional optical receiver is expressed by the following equation (2).
[0023]
(Equation 2)

[0024]
In the equation (2), for example, when Cpd = 0.3 pF and Lw = 1 nH, a resonance state occurs at about 9.2 GHz, and Zin becomes infinite. Therefore, from equation (1), the gain Zt is also infinite, and peaking occurs.
[0025]
On the other hand, in the present embodiment, it is possible to select a certain appropriate finite value as R1. In the configuration of FIG. 2, Zin is given by the following equation (3).
[0026]
[Equation 3]

[0027]
That is, even when Cpd and Lw are in a resonance state, Zin has a finite value, so that the value of the gain Zt does not greatly change from the expression (1). As a result, peaking can be suppressed, and an ideal output signal waveform can be obtained.
[0028]
FIG. 3 is a diagram showing the frequency characteristic of the gain of the transimpedance amplifier of the optical receiver of the present embodiment in comparison with the conventional one. In the conventional characteristic shown in FIG. 3A, peaking of about 8 dB occurs near 10 GHz. On the other hand, in the characteristics of the optical receiver of the present embodiment, good results are obtained as shown in FIG.
[0029]
FIG. 4 is a diagram illustrating the group delay characteristics of the transimpedance amplifier of the optical receiver according to the present embodiment in comparison with the related art. In the conventional characteristic shown in FIG. 4A, the group delay deviation sharply increases around 10 GHz where peaking occurs. On the other hand, as shown in FIG. 4B, the characteristics of the optical receiver according to the present embodiment show that the group delay deviation is very small over the entire frequency band.
[0030]
As described above, in the present embodiment, the resistor R1 connected in series between the photodiode PD and the power supply line, and the capacitor C1 connected between the power supply line and the ground potential inside the integrated circuit. And the peaking adjustment unit 41 is provided between the photodiode PD and its power supply line. Then, an appropriate value is set as the resistor R1, and a change in the value of the gain Zt is suppressed by causing Zin to take a finite value even when Cpd and Lw are in a resonance state. This prevents the occurrence of peaking.
[0031]
Thereby, even when the optical receiver of the present embodiment is used, for example, as a receiver for high-speed optical communication, peaking caused by connecting the photodiode PD and the amplifier 5 via the bonding wire is effectively suppressed. And a good signal without waveform deterioration can be output.
[0032]
(Second embodiment)
FIG. 5 is a functional block diagram showing a second embodiment of the optical receiver according to the present invention. In this embodiment, a variable characteristic peaking adjustment unit 42 (reference numeral 42 is provided for distinction from FIG. 1) is provided. Further, a peak detector 7 is provided between the amplifier 5 and the electric signal output unit 6, and the characteristic of the peaking adjusting unit 42 is controlled based on the peaking detection result of the peak detector 7.
[0033]
FIG. 6 is a circuit diagram showing an embodiment of the optical receiving device shown in FIG. 6, the peaking adjustment unit 42 includes resistors R1 and R2 having different resistance values. These resistors are switched by a peak detection signal provided from the peak detector 7 to vary the peaking suppression characteristic of the peaking adjustment unit 42. In FIG. 6, a capacitor C1 may be connected between a power supply line to the photodiode PD and a ground potential inside the integrated circuit. Further, instead of switching a plurality of resistors, a variable resistor may be used.
[0034]
FIG. 7 is a circuit diagram showing a configuration example of the peak detector 7 of FIG. In FIG. 7, a part of the electric output signal from the amplifier 5 is branched and inputted to differentiating circuits 421 and 422 having different frequency characteristics. Each of the differentiating circuits 421 and 422 outputs a differential value of the electric output signal in a different frequency band, and inputs the differential value to the subtractor 423. The subtractor 423 obtains the difference between the differential values and supplies the difference to the peaking adjustment unit as a peak detection signal.
[0035]
With such a configuration, the optical receiver according to the present embodiment can automatically adjust the peaking suppression characteristic to an optimum state in any use state. Therefore, the optical receiver of this embodiment can be widely used from a trunk system to home use.
[0036]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide an optical receiver and a peak detector that can suppress the peaking of the reception gain due to the inductance property of the bonding wire and thereby improve the reception performance.
[Brief description of the drawings]
FIG. 1 is a functional block diagram showing a first embodiment of an optical receiver according to the present invention.
FIG. 2 is a circuit diagram showing an embodiment of the optical receiving device shown in FIG.
FIG. 3 is a diagram showing a frequency characteristic of a gain of a transimpedance amplifier of the optical receiver according to the embodiment of the present invention, as compared with a conventional example.
FIG. 4 is a diagram showing a group delay characteristic of a transimpedance amplifier of the optical receiver according to the embodiment of the present invention, as compared with the related art.
FIG. 5 is a functional block diagram showing a second embodiment of the optical receiver according to the present invention.
FIG. 6 is a circuit diagram showing an embodiment of the optical receiver shown in FIG. 5;
FIG. 7 is a circuit diagram showing one configuration example of a peak detector 7 of FIG. 6;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical signal input part 2 ... Optical / electrical conversion element 3 ... Power supply voltage supply parts 41 and 42 ... Peaking adjustment part 5 ... Amplifier 6 ... Electric signal output part 7 ... Peak detector

Claims (8)

In an optical receiver, an optical signal is converted into an electric signal by an optical / electrical conversion element, and the electric signal is input into an integrated circuit and amplified by an amplifier in the integrated circuit.
Power supply means for supplying a power current to the optical / electrical conversion element through the inside of the integrated circuit;
Connecting means having a predetermined inductance component and connecting a power supply side terminal of the optical / electrical conversion element to the integrated circuit;
An optical receiving device, comprising: a peaking control unit provided between the power supply unit and the power supply terminal, for controlling peaking of the electric signal based on the inductance component. The peaking control means includes:
A resistance element provided in series in a connection path between a power supply side terminal of the light / electricity conversion element and the power supply means;
The optical receiver according to claim 1, further comprising a capacitor element provided in parallel between the resistance element and an internal ground potential of the integrated circuit. Further, the apparatus further includes peak detection means for detecting peaking in the amplified output of the amplifier and outputting a peak detection signal based on the result.
The optical receiving apparatus according to claim 1, wherein the peaking control unit controls peaking of the electric signal based on the peak detection signal. The optical receiving device according to claim 3, wherein the peaking control unit includes a variable resistance unit whose resistance value is changed based on the peak detection signal. The optical receiving device according to claim 4, wherein the variable resistance unit includes a plurality of resistance elements that are switched and connected to a power supply side terminal of the optical / electrical conversion element based on the peak detection signal. The peak detecting means,
First and second differentiating circuits to which amplified outputs of the amplifiers are respectively given and set to mutually different frequency bands;
The optical receiving apparatus according to claim 3, further comprising: a subtractor that generates the peak detection signal from a difference between the outputs of the first and second differentiating circuits. The optical receiving device according to claim 1, wherein the peaking control means is provided in the integrated circuit. An optical signal is converted into an electric signal by an optical / electrical conversion element, and the electric signal is provided in an optical receiver for inputting the electric signal into an integrated circuit and amplifying the signal by an amplifier in the integrated circuit. A peak detector for detecting,
First and second differentiating circuits to which amplified outputs of the amplifiers are respectively given and set to mutually different frequency bands;
A peak detector for detecting peaking in the amplified output of the amplifier based on a difference between outputs of the first and second differentiating circuits.

Images