JPH02156575A - Photo detector - Google Patents
Photo detectorInfo
- Publication number
- JPH02156575A JPH02156575A JP63311668A JP31166888A JPH02156575A JP H02156575 A JPH02156575 A JP H02156575A JP 63311668 A JP63311668 A JP 63311668A JP 31166888 A JP31166888 A JP 31166888A JP H02156575 A JPH02156575 A JP H02156575A
- Authority
- JP
- Japan
- Prior art keywords
- light
- light receiving
- receiving parts
- signals
- shielded
- 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
- 230000007257 malfunction Effects 0.000 abstract description 5
- 238000000034 method Methods 0.000 abstract description 5
- 239000004065 semiconductor Substances 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 239000004020 conductor Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 4
- 230000003287 optical effect Effects 0.000 description 4
- 239000000758 substrate Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
Landscapes
- Light Receiving Elements (AREA)
- Photo Coupler, Interrupter, Optical-To-Optical Conversion Devices (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は、フォトカブラ等の光結合半導体装置における
受光装置に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a light receiving device in an optically coupled semiconductor device such as a photocoupler.
〈従来技術〉
従来、光結合半導体装置において、外乱等による雑音を
除去するため、第4図および第5図に示す如く、受光装
置は、受光素子lとして一つの受光部2と、増幅器3お
よび比較器4を有する増幅回路5とから形成され、発光
素子6 (fill (入力側)と受光素子l側(出力
側)との間に存在する人出力間容ff1clを通して入
力端より出力側の受光部2へ入力する同相雑音信号を除
去するよう受光部2の表面上に光7を通す透明な導電膜
8が配置されている。<Prior Art> Conventionally, in an optically coupled semiconductor device, in order to remove noise due to disturbance etc., a light receiving device has one light receiving section 2 as a light receiving element l, an amplifier 3 and an amplifier 3, as shown in FIGS. It is formed from an amplifier circuit 5 having a comparator 4, and receives light from the input end to the output side through the human output capacity ff1cl that exists between the light emitting element 6 (input side) and the light receiving element l side (output side). A transparent conductive film 8 through which light 7 passes is arranged on the surface of the light receiving section 2 so as to remove common mode noise signals input to the section 2.
また、他の従来例として、第6図および第7図に示す如
く、受光部2の周囲に導電体9を配し、該導電体9から
の出力信号と、受光部2からの出力信号とを増幅器3
a、 3 bで夫々増幅した後、これらの値を差引する
ことにより同相雑音信号除去比(Coau++on M
ode Rejection flatio:以下CM
RRと呼ぶ)を高めて、同相入力による誤動作を少なく
している。In addition, as another conventional example, as shown in FIGS. 6 and 7, a conductor 9 is arranged around the light receiving section 2, and the output signal from the conductor 9 and the output signal from the light receiving section 2 are the amplifier 3
After a and 3 b are amplified, these values are subtracted to obtain the common-mode noise signal rejection ratio (Coau++ on M
ode Rejection flatio: CM below
(referred to as RR) to reduce malfunctions caused by common-mode input.
なお、図中、IOは半導体基板、11は基準電圧である
。Note that in the figure, IO is a semiconductor substrate, and 11 is a reference voltage.
く 発明が解決しようとする問題点 〉しかしながら、
第4図および第5図に示した従来の構成では、受光部2
上に透明導電膜8をつけるプロセスが必要であり、工程
の繁雑化と価格上昇が避けられないといった問題がある
。Problems that the invention seeks to solve 〉However,
In the conventional configuration shown in FIGS. 4 and 5, the light receiving section 2
A process for attaching a transparent conductive film 8 thereon is required, which poses problems such as complicated processes and an unavoidable increase in price.
また、第6図および第7図に示した従来の構成では、高
CMRRを得るには入力端と受光部2間の容量C3と、
入力側と導電体9間の容ff1c2とが等しくなること
が必要となるが、実際にフォトカブラのような光結合半
導体装置では、入力間の距離が受光部形状(通常0 、
5 mm11前後)に対し1山川以下と小さいため、容
量C2と03を合わせるために試行錯誤が必要であった
。In addition, in the conventional configuration shown in FIGS. 6 and 7, in order to obtain high CMRR, the capacitance C3 between the input end and the light receiving section 2,
It is necessary that the capacitance ff1c2 between the input side and the conductor 9 be equal, but in practice, in an optically coupled semiconductor device such as a photocoupler, the distance between the inputs is determined by the shape of the light receiving part (usually 0,
Since the capacitance is small (less than 1 mountain river) compared to around 5 mm11), trial and error was necessary to match the capacitances C2 and 03.
また、C2と03が合致しても、受光部2および受光部
2への入出力間容fiC3が入力となる増幅器3aと、
導電体9および導電体9の人出方間容量C2が人力する
増幅器3bとでは、回路の応答特性が一致しなくなるた
め高CMRI”tを得ることが困難であった。In addition, even if C2 and 03 match, the amplifier 3a whose input is the light receiving section 2 and the input/output capacity fiC3 to the light receiving section 2,
With the amplifier 3b in which the capacitance C2 between the conductor 9 and the output side of the conductor 9 is manually operated, it is difficult to obtain a high CMRI't because the response characteristics of the circuits do not match.
本発明は、上記問題点に鑑み、高CMRRを容易に達成
することができる受光装置の提供を目的とする。In view of the above problems, the present invention aims to provide a light receiving device that can easily achieve high CMRR.
く 問題点を解決するための手段 〉
本発明による問題点解決手段は、第1図〜第3図の如く
、発光素子6からの光7を受光する受光装置において、
遮光されていない複数の受光部12a12bと、該受光
部12a、12bと同数の遮光された遮光受光部13a
、13bとが点対称位置に配置され、前記遮光されてい
ない受光部12a、12bの出力信号と遮光された遮光
受光部13a、13bの出力信号とを増幅比較する増幅
回路14を備えたものである。Means for Solving the Problems> The means for solving the problems according to the present invention is as shown in FIGS. 1 to 3, in a light receiving device that receives light 7 from a light emitting element 6,
A plurality of unshielded light receiving sections 12a12b and the same number of light receiving sections 12a and 12b as light-shielded light receiving sections 13a.
, 13b are arranged point-symmetrically, and includes an amplifier circuit 14 for amplifying and comparing the output signals of the unshielded light receiving sections 12a, 12b and the output signals of the shielded light receiving sections 13a, 13b. be.
〈作用〉
上記問題点解決手段において、受光部12a、12bか
らの信号は、合成されて増幅回路14に出力される。一
方、遮光受光部13a、+3bからの信号も同様に合成
されて増幅回路14に出力される。そして、それぞれの
出力信号は、増幅比較されて出力される。<Operation> In the above problem solving means, the signals from the light receiving sections 12a and 12b are combined and output to the amplifier circuit 14. On the other hand, signals from the light shielding light receiving sections 13a and +3b are similarly combined and output to the amplifier circuit 14. The respective output signals are then amplified and compared and output.
ここで、受光装置に入力した雑音信号は、受光部が4分
割されて、かつ点対称配置になっているため、受光部t
2a、12bと遮光受光部13a、13bには同一じ量
の出力信号を生じる。したがって、増幅回路I4によっ
て、受光部12a、+2bからの信号と遮光受光部13
a、+3bからの信号が互いに相殺し合うため、雑音信
号による誤動作は生じない。Here, the noise signal input to the light receiving device is transmitted to the light receiving portion t because the light receiving portion is divided into four parts and arranged point symmetrically.
2a, 12b and the light-shielding light receiving sections 13a, 13b produce output signals of the same amount. Therefore, the amplifier circuit I4 combines the signals from the light receiving sections 12a and +2b with the light-shielding light receiving section 13.
Since the signals from a and +3b cancel each other out, malfunctions due to noise signals do not occur.
また、増幅回路14の増幅器は、受光部12a12bお
よび遮光受光部13a、13bに対して同一の構成とな
っており、かつそれぞれの人力も同一構成の受光部とな
っているので、回路応答に違いは生じないため、同相入
力信号が出力されないので、より高いCMRRが可能と
なる。In addition, the amplifier of the amplifier circuit 14 has the same configuration for the light receiving section 12a12b and the light-shielding light receiving sections 13a and 13b, and each light receiving section has the same configuration, so there is no difference in circuit response. Since no in-phase input signal is generated, a higher CMRR is possible.
一方、発光素子6から発せられた光信号に対しては、遮
光されていない受光部12a、12bにのみ信号が入る
ため、光信号の検出が確実に行なわれる。On the other hand, since the optical signal emitted from the light emitting element 6 enters only the light receiving sections 12a and 12b which are not shielded from light, the optical signal can be detected reliably.
したがって、受光素子1の受光部を遮光されていないも
のと、遮光されたものに2分割することによって、雑音
信号が相殺されて除去されるため、CMRRを大きくす
ることができる。Therefore, by dividing the light-receiving portion of the light-receiving element 1 into two parts, one that is not shielded and the other that is shielded, the noise signals are canceled out and removed, so that the CMRR can be increased.
しかも、受光素子lの製造過程において、受光素子1の
表面に遮光体L5a、15bを被せるだけでよく、簡単
なプロセスで製造できるため、容易に高いCMRRを有
する受光装置を供給することができろ。Moreover, in the manufacturing process of the light receiving element 1, it is only necessary to cover the surface of the light receiving element 1 with the light shielding bodies L5a and 15b, and the manufacturing process is simple, so it is possible to easily provide a light receiving device with high CMRR. .
〈実施例〉
以下、本発明の実施例を第1図および第2図に基づいて
説明する。第1図は本発明の実施例を示す受光装置の平
面図、第2図は同じく受光装置の電気回路図、第3図は
発光素子および受光素子の位置関係を示す図である。<Example> Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2. FIG. 1 is a plan view of a light receiving device showing an embodiment of the present invention, FIG. 2 is an electric circuit diagram of the same, and FIG. 3 is a diagram showing the positional relationship between a light emitting element and a light receiving element.
本発明受光装置の受光素子lは、図示の如く、半導体基
板lO上に遮光されてない2個の受光部+2a、12b
と、該受光部12a、12bと同数の遮光された2gの
遮光受光部13a、13bとが、発光素子6からの光7
を均等に受光できるよう点対称位置に配置されている。As shown in the figure, the light-receiving element l of the light-receiving device of the present invention includes two light-receiving parts +2a and 12b that are not shielded from light on a semiconductor substrate lO.
2g of light-shielded light-receiving parts 13a, 13b, which are the same number as the light-receiving parts 12a, 12b, receive the light 7 from the light-emitting element 6.
They are placed in symmetrical positions so that they can receive light evenly.
そして、前記遮光されていない受光部12a、12bの
出力信号と遮光された遮光受光部13a、13bの出力
信号とを増幅比較する増幅回路14を備えている。Further, an amplifier circuit 14 is provided which amplifies and compares the output signals of the unshielded light receiving sections 12a, 12b and the output signals of the shielded light receiving sections 13a, 13b.
前記受光部12a、12bおよび遮光受光部13a。The light receiving sections 12a, 12b and the light-shielding light receiving section 13a.
tabは、フォトダイオードからなり、該遮光受光部1
3a、13bは、その表面をメタルあるいは不透明な絶
縁体等の遮光体15a、15bで覆われている。なお、
発光索子6は発光ダイオードからなる。tab is composed of a photodiode, and the light-shielding light receiving section 1
The surfaces of the elements 3a and 13b are covered with light shielding members 15a and 15b made of metal or an opaque insulator. In addition,
The light emitting cord 6 consists of a light emitting diode.
また、前記増幅回路14は、受光部とともに一枚の半導
体基板lO上に装着されており、前記受光部12a、1
2bからの出力信号を増幅する増幅器16aと、前記遮
光受光部13a、13bからの出力信号を増幅する増幅
H+516bと、両槽幅器16a。Further, the amplifying circuit 14 is mounted on a single semiconductor substrate 1O together with the light receiving sections, and the light receiving sections 12a, 1
2b, an amplifier H+516b that amplifies the output signals from the light-shielding light-receiving sections 13a and 13b, and a double-channel width transducer 16a.
16bからの出力を比較して検出信号を出力する比較器
17とから構成されている。両槽幅器I6a、16bは
、同一の回路から構成されており、また受光部12a、
12bおよび遮光受光部13a、13bは、それぞれの
増幅器16a、16bに対して並列に接続されている。The comparator 17 compares the outputs from the detector 16b and outputs a detection signal. Both tank width gauges I6a and 16b are composed of the same circuit, and the light receiving parts 12a,
12b and the light shielding light receiving sections 13a, 13b are connected in parallel to the respective amplifiers 16a, 16b.
そして、発光素子6と受光部12a、12bとの間の人
出方間容量は、それぞれC4およびC5とされる。また
、遮光受光部13a、13bとの間の人出方間容量はC
6およびC7とされる。The capacity between the light emitting element 6 and the light receiving sections 12a and 12b is C4 and C5, respectively. In addition, the capacity between the light shielding light receiving parts 13a and 13b is C
6 and C7.
上記構成において、受光部12a、12bからの信号は
、合成されて増幅器16aにより増幅される。一方、遮
光受光部13a、13bからの信号も同様に合成されて
増幅器16bにより増幅される。In the above configuration, the signals from the light receiving sections 12a and 12b are combined and amplified by the amplifier 16a. On the other hand, signals from the light shielding light receiving sections 13a and 13b are similarly combined and amplified by the amplifier 16b.
そして、それぞれの増幅器16a、16bの出力は、比
較器I7で比較されてデジタル出力される。The outputs of the respective amplifiers 16a and 16b are compared by a comparator I7 and output digitally.
ここで、入力端から人出力間容IC4〜C7を通して出
力側に入る同相雑音信号は、受光素子1が4分割されて
、かつ点対称配置になっているため、第3図の如く同じ
量の雑音信号電流を生じる。Here, the common mode noise signal entering the output side from the input end through the human output capacitors IC4 to C7 has the same amount as shown in FIG. Generates a noise signal current.
すなわち、第3図において、雑音信号が直交するX、Y
軸座標のX軸上から入光するものとすると、雑音信号電
流部から受光部12aおよび遮光受光部13aの中心ま
での距離が等しくなり、その容量C4と06とは等しく
なる。同様に、受光部12bと遮光受光部13bとの間
の容ff1c5と07とは等しくなる。そのため、受光
部12a、12bと遮光受光部13a、13bには同じ
量の雑音信号電流を生じる。That is, in FIG. 3, the noise signals are orthogonal to each other
Assuming that light enters from on the X-axis of the axial coordinates, the distances from the noise signal current section to the centers of the light receiving section 12a and the light-shielding light receiving section 13a are equal, and the capacitances C4 and 06 thereof are equal. Similarly, the capacities ff1c5 and 07 between the light receiving section 12b and the light-shielding light receiving section 13b are equal. Therefore, the same amount of noise signal current is generated in the light receiving sections 12a, 12b and the light shielding light receiving sections 13a, 13b.
したがって、同じ里の雑音信号電流が、同一回路構成を
持つ増幅器16a、16bにより増幅され、差動人力の
比較器17に入力しても、出力は反転せず、受光部12
a、12bからの信号と遮光受光部13a、13bから
の信号が互いに相殺し合って出力信号が出されるため、
雑音信号による比較器I7の誤動作は生じない。Therefore, even if the same noise signal current is amplified by the amplifiers 16a and 16b having the same circuit configuration and input to the differential human power comparator 17, the output will not be inverted and the light receiving section 12
Since the signals from a and 12b and the signals from the light-shielding light receiving sections 13a and 13b cancel each other out, an output signal is output.
Malfunction of comparator I7 due to noise signals does not occur.
また、各増幅器16a、16bの人力は、受光部+2a
、12bあるいは遮光受光部+3a、13bのように、
受光部2つからなる同一の構成となっており、回路応答
に違いは生じないため、同相入力信号が出力されないの
で、より高いCMRRが可能となる。In addition, the human power of each amplifier 16a, 16b is the light receiving part +2a
, 12b or the light-shielding light receiving part +3a, 13b,
Since they have the same configuration consisting of two light receiving sections and there is no difference in circuit response, no in-phase input signal is output, making it possible to achieve higher CMRR.
一方、発光素子6から発せられた光信号に対しては、遮
光されていない受光部12a12bにのみ信号が入るた
め、光信号の検出が確実に行なわれる。On the other hand, since the optical signal emitted from the light emitting element 6 enters only the light receiving section 12a12b which is not shielded from light, the optical signal can be detected reliably.
したがって、受光素子lを遮光されていないものと、遮
光されたしのに2分割することによって、同相入力信号
が相殺されて除去されるため、CMRRを大きくするこ
とができる。Therefore, by dividing the light-receiving element l into two, one that is not shielded and the other that is shielded, the in-phase input signals are canceled out and removed, so that the CMRR can be increased.
しかも、受光素子1の製造過程において、受光素子lの
表面に遮光体15a、15bを被せるだけでよく、受光
素子lに導電膜を貼り付けるプロセスに比べて簡単なプ
ロセスで製造できるため、製造上のプロセスを変更する
必要がなく、容易に高いCMRRを有する光結合半導体
装置を供給することができる。Moreover, in the manufacturing process of the light receiving element 1, it is only necessary to cover the surface of the light receiving element l with the light shielding bodies 15a and 15b, and the manufacturing process is simpler than that of pasting a conductive film on the light receiving element l. There is no need to change the process, and an optically coupled semiconductor device having high CMRR can be easily provided.
なお、本発明は、上記実施例に限定されるものではなく
、本発明の範囲内で上記実施例に多くの修正および変更
を加え得ることは勿論である。It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.
たとえば、受光素子lは4分割に限らず、点対称に6分
割以上にしてもよい。For example, the light receiving element l is not limited to four divisions, but may be divided into six or more points symmetrically.
〈発明の効果〉
以上の説明から明らかな通り、本発明によると、発光素
子からの光を受光ずろ受光装置において、遮光されてい
ない複数の受光部と、該受光部と同数の遮光された遮光
受光部とが点対称位置に配置され、前記遮光されていな
い受光部の出力信号と遮光された遮光受光部の出力信号
とを増幅比較する増幅回路を備えることにより、雑音信
号を相殺して除去できるため、CMRRを大きくするこ
とかできる。<Effects of the Invention> As is clear from the above description, according to the present invention, in a staggered light receiving device that receives light from a light emitting element, there are a plurality of unshielded light receiving sections and the same number of light receiving sections as the light receiving sections. The light receiving section is arranged point-symmetrically with the light receiving section, and the noise signal is canceled out and removed by providing an amplifier circuit that amplifies and compares the output signal of the unshielded light receiving section and the output signal of the light shielded light receiving section. Therefore, the CMRR can be increased.
しかも、受光素子の製造過程において、簡単なプロセス
で製造できるため、容易に高いCMRRを有する受光装
置を供給することができるといった優れた効果がある。Furthermore, since the light receiving element can be manufactured through a simple process, it has the advantageous effect that a light receiving device having a high CMRR can be easily provided.
第1図本発明の実施例を示す受光装置の平面図、第2図
は同じく受光装置の電気回路図、第3図は発光素子およ
び受光素子の位置関係を示す図、第4図は従来の受光装
置の平面図、第5図はその電気回路図、第6図は他の従
来例の受光装置の平面図、第7図はその電気回路図であ
る。
l;受光素子、6:発光素子、7:光、12a、12b
:受光部、13a、13b:遮光受光部、14.増幅回
路、I 5a、 l 5b:遮光体、I 6a、 I
6b:増幅器、17:比較器。
出 願 人 シャープ株式会社Fig. 1 is a plan view of a light receiving device showing an embodiment of the present invention, Fig. 2 is an electric circuit diagram of the same, Fig. 3 is a diagram showing the positional relationship between a light emitting element and a light receiving element, and Fig. 4 is a plan view of a conventional light receiving device. FIG. 5 is a plan view of the light receiving device, FIG. 5 is its electric circuit diagram, FIG. 6 is a plan view of another conventional light receiving device, and FIG. 7 is its electric circuit diagram. l; Light receiving element, 6: Light emitting element, 7: Light, 12a, 12b
: Light receiving section, 13a, 13b: Light shielding light receiving section, 14. Amplifier circuit, I 5a, I 5b: Light shield, I 6a, I
6b: Amplifier, 17: Comparator. Applicant Sharp Corporation
Claims (1)
れていない複数の受光部と、該受光部と同数の遮光され
た遮光受光部とが点対称位置に配置され、前記遮光され
ていない受光部の出力信号と遮光された遮光受光部の出
力信号とを増幅比較する増幅回路を備えたことを特徴と
する受光装置。In a light-receiving device that receives light from a light-emitting element, a plurality of unshielded light-receiving parts and the same number of light-shielded light-receiving parts as the light-receiving parts are arranged in point-symmetrical positions, and the unshielded light-receiving parts 1. A light-receiving device comprising an amplifier circuit that amplifies and compares the output signal of the light-shielded light-receiving section with the output signal of the light-shielded light-receiving section.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP31166888A JPH07105524B2 (en) | 1988-12-08 | 1988-12-08 | Light receiving device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP31166888A JPH07105524B2 (en) | 1988-12-08 | 1988-12-08 | Light receiving device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH02156575A true JPH02156575A (en) | 1990-06-15 |
JPH07105524B2 JPH07105524B2 (en) | 1995-11-13 |
Family
ID=18020046
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP31166888A Expired - Fee Related JPH07105524B2 (en) | 1988-12-08 | 1988-12-08 | Light receiving device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH07105524B2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08335712A (en) * | 1995-04-05 | 1996-12-17 | Matsushita Electron Corp | Photodetector and its manufacture |
JP2002217447A (en) * | 2001-01-16 | 2002-08-02 | Toshiba Corp | Semiconductor photodetector and semiconductor light receiving and transmission system |
US6525858B1 (en) | 1997-06-04 | 2003-02-25 | Nec Corporation | Optical receiver and optical network system using thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4942295A (en) * | 1972-03-03 | 1974-04-20 | ||
JPS60158756U (en) * | 1984-03-30 | 1985-10-22 | 富士ゼロックス株式会社 | Photo interrupter |
-
1988
- 1988-12-08 JP JP31166888A patent/JPH07105524B2/en not_active Expired - Fee Related
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4942295A (en) * | 1972-03-03 | 1974-04-20 | ||
JPS60158756U (en) * | 1984-03-30 | 1985-10-22 | 富士ゼロックス株式会社 | Photo interrupter |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08335712A (en) * | 1995-04-05 | 1996-12-17 | Matsushita Electron Corp | Photodetector and its manufacture |
US6525858B1 (en) | 1997-06-04 | 2003-02-25 | Nec Corporation | Optical receiver and optical network system using thereof |
JP2002217447A (en) * | 2001-01-16 | 2002-08-02 | Toshiba Corp | Semiconductor photodetector and semiconductor light receiving and transmission system |
Also Published As
Publication number | Publication date |
---|---|
JPH07105524B2 (en) | 1995-11-13 |
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