JPH05292101A - Communication equipment - Google Patents

Communication equipment

Info

Publication number
JPH05292101A
JPH05292101A JP9289492A JP9289492A JPH05292101A JP H05292101 A JPH05292101 A JP H05292101A JP 9289492 A JP9289492 A JP 9289492A JP 9289492 A JP9289492 A JP 9289492A JP H05292101 A JPH05292101 A JP H05292101A
Authority
JP
Japan
Prior art keywords
signal
level
point
circuit
communication line
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
Application number
JP9289492A
Other languages
Japanese (ja)
Inventor
Masashi Takada
雅司 高田
Takashi Kimura
隆志 木村
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nissan Motor Co Ltd
Original Assignee
Nissan Motor Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nissan Motor Co Ltd filed Critical Nissan Motor Co Ltd
Priority to JP9289492A priority Critical patent/JPH05292101A/en
Publication of JPH05292101A publication Critical patent/JPH05292101A/en
Pending legal-status Critical Current

Links

Landscapes

  • Dc Digital Transmission (AREA)
  • Small-Scale Networks (AREA)

Abstract

PURPOSE:To improve the leading characteristic of a signal of either an H or L level and to attain high speed communication by providing 1st and 2nd transistors(TRs) outputting respectively the signal at H and L levels to the equipment so as to control the drive of the 1st TR with a timing circuit. CONSTITUTION:When a signal level at a point A inverts to OV from 5V, an output signal of an inverter 51a goes to a high level, an output signal of a timer circuit 51b goes to a high level by a prescribed time td and an output signal of a NAND gate 51c goes to a low level by the prescribed time td. Thus, a P-channel MOS TR 52 is turned on by the prescribed time td. In this case a gate voltage of an N-channel MOS TR 53 is at a low level and then the TR 53 is turned off. Thus, a level at a point B reaches 5V after a time t2 by a current flowing from the TR 52. Since the ON-resistance of the TR 52 is far smaller than the resistance of the resistor 54, an unsharpened rising waveform of the signal due to a stray capacitance in existence between a communication line 20 and ground is far better corrected in comparison with the case of the level at the point B increased by a current limited by the resistor 54.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、複数個の通信ユニット
間で通信線を介して信号を授受する通信装置に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication device for exchanging signals between a plurality of communication units via communication lines.

【0002】[0002]

【従来の技術】この種の通信装置は、例えば図4に示す
ように複数個の多重通信ユニット10A、10B……1
0Nを通信線20で接続してなり、各通信ユニット10
は図5に示すように、ハイレベル信号およびローレベル
信号を択一的に生成して通信線20に出力する送信回路
11と、その送信回路11がハイレベル信号またはロー
レベル信号を出力するようにその送信回路11に制御信
号を入力する送信制御回路12と、通信線20上の信号
を受信する受信回路13と、送信制御回路12を制御す
る通信制御回路14と、この通信制御回路14を制御す
る中央制御回路15とを備えてなる。
2. Description of the Related Art A communication apparatus of this type is composed of a plurality of multiplex communication units 10A, 10B ... 1 as shown in FIG.
0N is connected by a communication line 20, and each communication unit 10
As shown in FIG. 5, a transmission circuit 11 that selectively generates a high level signal and a low level signal and outputs the high level signal and the low level signal to the communication line 20, and the transmission circuit 11 outputs a high level signal or a low level signal. A transmission control circuit 12 for inputting a control signal to the transmission circuit 11, a reception circuit 13 for receiving a signal on the communication line 20, a communication control circuit 14 for controlling the transmission control circuit 12, and the communication control circuit 14. And a central control circuit 15 for controlling.

【0003】図6はたとえば実開平2−51437号公
報に開示されているこの種の通信装置に用いられる送信
回路11A,11B……の従来例である。電源電位VDD
と接地電位VCCとの間には、抵抗111とN型MOSト
ランジスタ112とが直列に接続され、N型MOSトラ
ンジスタ112のゲートには送信制御回路12からの送
信制御信号が接続され、ドレインには通信線20が接続
される。他の通信ユニット10Bの送信回路11Bも全
く同様に構成される。
FIG. 6 shows a conventional example of transmission circuits 11A, 11B ... Used in a communication device of this type disclosed in Japanese Utility Model Laid-Open No. 2-51437. Power supply potential V DD
The resistor 111 and the N-type MOS transistor 112 are connected in series between the ground potential V CC and the ground potential V CC , the transmission control signal from the transmission control circuit 12 is connected to the gate of the N-type MOS transistor 112, and the drain is connected to the drain. Is connected to the communication line 20. The transmission circuit 11B of the other communication unit 10B has the same configuration.

【0004】図7は図6の送信回路のA点、B点の信号
波形を示し、A点のレベルが0Vから5Vに反転すると
N型MOSトランジスタ112がオンしてB点のレベル
は急速に0Vとなる。次にA点のレベルが反転して5V
から0VになるとN型MOSトランジスタ112がオフ
してB点のレベルが5Vになる。このように、A点の信
号レベル、つまり送信制御回路12から送信回路11に
入力される送信制御信号の信号レベルに応じて通信線2
0にハイレベルまたはローレベルの信号が出力される。
FIG. 7 shows signal waveforms at points A and B of the transmission circuit of FIG. 6, and when the level at point A is inverted from 0V to 5V, the N-type MOS transistor 112 turns on and the level at point B rapidly. It becomes 0V. Next, the level at point A is reversed and 5V
From 0V to 0V, the N-type MOS transistor 112 turns off and the level at point B becomes 5V. In this way, the communication line 2 corresponds to the signal level at the point A, that is, the signal level of the transmission control signal input from the transmission control circuit 12 to the transmission circuit 11.
A high level or low level signal is output to 0.

【0005】[0005]

【発明が解決しようとする課題】しかしながら、図7の
B点の波形から分かる通り、通信線20にハイレベル信
号を出力する際、通信線20と接地間の浮遊容量30
(図6)に起因してB点の信号の立上がりがなまる(A
点のレベルが反転してから5Vに達するまでに遅延時間
1を要する)傾向にある。同様にB点の信号の立下が
りもなまる(A点のレベルが反転してから0Vに達する
までに遅延時間t3を要する)が、t1とt3を比較する
とt1の方が大きくなる。これは、t1が抵抗111の抵
抗値および浮遊容量30の容量値に比例し、t3がN型
MOSトランジスタ112のオン抵抗および浮遊容量3
0の容量値に比例しており、抵抗111の抵抗値をN形
MOSトランジスタ112のオン抵抗よりも十分大きく
する必要があるためである。そのため、A点の0V信号
の時間間隔thをt1以上にせざるを得ず、高速通信に
支障をきたしている。
However, as can be seen from the waveform at point B in FIG. 7, when outputting a high level signal to the communication line 20, the stray capacitance 30 between the communication line 20 and the ground is reduced.
Due to (Fig. 6), the rising edge of the signal at point B becomes dull (A
It takes a delay time t 1 from the point level is inverted until it reaches 5V). Similarly, the trailing edge of the signal at point B also becomes dull (a delay time t 3 is required from when the level at point A is inverted until it reaches 0 V), but when t 1 and t 3 are compared, t 1 is greater. Become. This is because t 1 is proportional to the resistance value of the resistor 111 and the capacitance value of the stray capacitance 30, and t 3 is the ON resistance of the N-type MOS transistor 112 and the stray capacitance 3
This is because it is proportional to the capacitance value of 0 and the resistance value of the resistor 111 needs to be sufficiently larger than the ON resistance of the N-type MOS transistor 112. Therefore, the time interval th of the 0V signal at the point A must be set to be t 1 or more, which hinders high-speed communication.

【0006】本発明の目的は、通信線と接地間の浮遊容
量による遅延の影響を低減し、高速通信が可能な通信装
置を提供することにある。
An object of the present invention is to provide a communication apparatus capable of reducing the influence of delay due to a stray capacitance between the communication line and the ground and enabling high speed communication.

【0007】[0007]

【課題を解決するための手段】一実施例を示す図1に対
応付けて説明すると、本発明、ハイレベル信号およびロ
ーレベル信号を択一的に生成して通信線20に出力する
送信回路50A,50B……と、送信回路50A,50
B……がハイレベル信号またはローレベル信号を出力す
るようにその送信回路に制御信号を入力する送信制御回
路12(図5)とを備えた複数個の通信ユニット10
A,10B……(図4)間で通信線20を介して信号を
授受する通信装置に適用される。そして上記目的は送信
回路50A,50B……を次のように構成して達成され
る。送信回路50A,50B……は、上記制御信号が第
1のレベルから第2のレベルに反転するときに所定時間
だけタイミング信号を出力するタイミング回路51と、
そのタイミング信号に応答して通信線20にハイレベル
またはロ−レベルのいずれか一方のレベルの信号を出力
する第1のトランジスタ52と、制御信号が第2のレベ
ルから第1のレベルに反転するのに応答して通信線20
に他方のレベルの信号を出力する第2のトランジスタ5
3とを具備する。
A transmission circuit 50A according to the present invention, which selectively generates a high level signal and a low level signal and outputs them to a communication line 20, will be described with reference to FIG. 1 showing an embodiment. , 50B ... and the transmission circuits 50A, 50
A plurality of communication units 10 including a transmission control circuit 12 (FIG. 5) for inputting a control signal to the transmission circuit so that B ... Outputs a high level signal or a low level signal.
It is applied to a communication device that transmits and receives signals between A, 10B ... (FIG. 4) via the communication line 20. The above object is achieved by configuring the transmitting circuits 50A, 50B ... As follows. The transmission circuits 50A, 50B, ... Include a timing circuit 51 that outputs a timing signal for a predetermined time when the control signal is inverted from the first level to the second level,
In response to the timing signal, the first transistor 52 that outputs a signal of either high level or low level to the communication line 20, and the control signal is inverted from the second level to the first level. In response to communication line 20
Second transistor 5 which outputs the signal of the other level to
3 and 3.

【0008】[0008]

【作用】制御信号が第1のレベルから第2のレベルに反
転するときに所定時間だけ出力されるタイミング信号に
応答して、第1のトランジスタ52は通信線20に例え
ばハイレベル信号を出力する。制御信号が第2のレベル
から第1のレベルに反転するのに応答して第2のトラン
ジスタ53は通信線20に例えばローレベル信号を出力
する。
In response to the timing signal output for a predetermined time when the control signal is inverted from the first level to the second level, the first transistor 52 outputs, for example, a high level signal to the communication line 20. .. In response to the control signal being inverted from the second level to the first level, the second transistor 53 outputs, for example, a low level signal to the communication line 20.

【0009】なお、本発明の構成を説明する上記課題を
解決するための手段と作用の項では、本発明を分かり易
くするために実施例の図を用いたが、これにより本発明
が実施例に限定されるものではない。
Incidentally, in the section of means and action for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for making the present invention easy to understand. It is not limited to.

【0010】[0010]

【実施例】図1〜図3により本発明の1実施例を説明す
る。図1は送信回路50A,50B……(以下、単に符
号50で示すこともある)の詳細を示す図で、送信回路
50は、インバータ51a、タイマ回路51b、および
ナンドゲート51cを有するタイミング回路51と、タ
イミング回路51の出力信号でオン・オフするP型MO
Sトランジスタ52と、タイミング回路51の入力信号
でオン・オフするN型MOSトランジスタ53と、MO
Sトランジスタ52,53がオフのときの送信回路50
の出力信号レベルを規定する抵抗54とを有する。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing the details of the transmission circuits 50A, 50B ... (Simply denoted by reference numeral 50 hereinafter). The transmission circuit 50 includes a timing circuit 51 having an inverter 51a, a timer circuit 51b, and a NAND gate 51c. , P-type MO turned on / off by the output signal of the timing circuit 51
An S-transistor 52, an N-type MOS transistor 53 that is turned on / off by an input signal of the timing circuit 51, and an MO
Transmitting circuit 50 when the S transistors 52 and 53 are off
Of the output signal level of the resistor 54.

【0011】このように構成された送信回路50の動作
を図2を参照して説明する。A点の信号レベルが5Vの
ときP型MOSトランジスタ52はオフするため、B点
の信号レベルは0Vになっている。A点の信号レベルが
5Vから0Vに反転すると、インバータ51Aの出力信
号はハイレベルに、タイマ回路51bの出力信号は所定
時間tdだけハイレベルになり、ナンドゲート51cの
出力信号は所定時間tdだけローレベルとなる。このた
め、P型MOSトランジスタ52は時間td(図2のC
点の信号波形)だけオンする。このとき、N型MOSト
ランジスタ53のゲート電圧はローレベルであり、N型
MOSトランジスタ53はオフしている。したがって、
B点のレベルはP型MOSトランジスタ52から流れ込
む電流により時間t2後に5Vになる。
The operation of the transmission circuit 50 thus constructed will be described with reference to FIG. Since the P-type MOS transistor 52 is turned off when the signal level at the point A is 5V, the signal level at the point B is 0V. When the signal level at the point A is inverted from 5V to 0V, the output signal of the inverter 51A goes high, the output signal of the timer circuit 51b goes high for a predetermined time td, and the output signal of the NAND gate 51c goes low for a predetermined time td. It becomes a level. Therefore, the P-type MOS transistor 52 has a time td (C in FIG. 2).
Only the signal waveform at the point is turned on. At this time, the gate voltage of the N-type MOS transistor 53 is at low level, and the N-type MOS transistor 53 is off. Therefore,
The level at point B becomes 5 V after time t 2 due to the current flowing from the P-type MOS transistor 52.

【0012】ここで、P型MOSトランジスタ52のオ
ン抵抗は抵抗54の抵抗値(従来回路の抵抗111の抵
抗値)よりも格段に小さいから、従来のように抵抗54
(111)で制限された電流でB点の電位が上昇する場
合に比べて、通信線20と接地間の浮遊容量による信号
の立上がり波形のなまりは格段に是正される。すなわ
ち、B点の電位が0V→5Vになる時間は、従来例では
1に対して本実施例ではt2(<t1)となる。したが
って、A点のローレベルの時間th(図2)も短縮でき
るから、従来に比べて高速な通信が可能になる。
Since the ON resistance of the P-type MOS transistor 52 is much smaller than the resistance value of the resistance 54 (resistance value of the resistance 111 of the conventional circuit), the resistance 54 is the same as in the conventional case.
As compared with the case where the potential at the point B rises due to the current limited by (111), the rounding of the rising waveform of the signal due to the stray capacitance between the communication line 20 and the ground is significantly corrected. That is, the time at which the potential at the point B changes from 0 V to 5 V is t 1 in the conventional example, and t 2 (<t 1 ) in the present embodiment. Therefore, the low-level time th (FIG. 2) at the point A can be shortened, so that high-speed communication becomes possible as compared with the conventional case.

【0013】なお、図3に示すように、通信ユニット1
0Bの送信回路50Bから通信ユニット10Aの送信回
路50Aとは異なるレベル(5Vと0V)の信号を出力
する場合、送信回路50BのAB点に5Vの信号が入力
されるとN型MOSトランジスタ53Bがオンするか
ら、送信回路50AのP型MOSトランジスタ52がオ
ンしている間(時間td)、過大電流が送信回路50B
のN型MOSトランジスタ53に流れ込む。そのため、
タイマ回路51bの計時時間tdはできるだけ短かく設
定して、送信回路50BのN型MOSトランジスタ53
の破損を防止するように考慮する必要がある。
As shown in FIG. 3, the communication unit 1
When outputting the signals of different levels (5V and 0V) from the transmission circuit 50B of 0B the transmission circuit 50A of the communication unit 10A, when the signal of 5V is input to the A B point of the transmission circuit 50B N-type MOS transistor 53B Is turned on, an excessive current is generated while the P-type MOS transistor 52 of the transmission circuit 50A is turned on (time td).
Of the N-type MOS transistor 53. for that reason,
The time td of the timer circuit 51b is set as short as possible, and the N-type MOS transistor 53 of the transmitter circuit 50B is set.
Consideration must be given to prevent damage to the.

【0014】なお以上では、1本の通信線で複数種類の
情報を通信する多重通信装置を例にして説明したが、本
発明は多重通信装置に限定されるものではない。また、
タイミング回路51の構成も実施例に限定されないほ
か、各部信号のレベルも実施例の場合と逆の論理となる
ように回路を構成することもできる。
In the above description, the multiplex communication device for communicating a plurality of types of information over one communication line has been described as an example, but the present invention is not limited to the multiplex communication device. Also,
The configuration of the timing circuit 51 is not limited to that of the embodiment, and the circuit can be configured so that the level of the signal of each part has the opposite logic to that of the embodiment.

【0015】[0015]

【発明の効果】以上詳細に説明したように、本発明によ
れば、ハイレベルおよびロ−レベルのいずれか一方のレ
ベルの信号出力用の第1のトランジスタと他方のレベル
の信号出力用の第2のトランジスタを設け、第1のトラ
ンジスタを駆動制御するタイミング回路を設けるように
したから、一方のレベルの信号の立上がり特性が改善さ
れて高速な通信が可能となる。
As described above in detail, according to the present invention, the first transistor for signal output of either one of the high level and the low level and the first transistor for signal output of the other level. Since the second transistor is provided and the timing circuit for driving and controlling the first transistor is provided, the rising characteristic of the signal of one level is improved and high-speed communication becomes possible.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明に係る通信装置の2つの送信回路の一例
を示す図
FIG. 1 is a diagram showing an example of two transmission circuits of a communication device according to the present invention.

【図2】図1の送信回路の各部の信号波形を示す図FIG. 2 is a diagram showing signal waveforms of respective parts of the transmission circuit of FIG.

【図3】論理が反転した送信信号の波形図FIG. 3 is a waveform diagram of a transmission signal whose logic is inverted.

【図4】通信装置の概略を示す図FIG. 4 is a diagram showing an outline of a communication device.

【図5】通信ユニットの概略構成を示す図FIG. 5 is a diagram showing a schematic configuration of a communication unit.

【図6】従来の2つの送信回路の一例を示す図FIG. 6 is a diagram showing an example of two conventional transmission circuits.

【図7】従来の送信回路の各部の波形を示す図FIG. 7 is a diagram showing waveforms at various parts of a conventional transmission circuit.

【符号の説明】[Explanation of symbols]

10 通信ユニット 12 送信制御回路 20 通信線 50A,50B…… 送信回路 51 タイミング回路 51a インバータ 51b タイマ回路 51c ナンドゲート 52 P型MOSトランジスタ 53 N型MOSトランジスタ 54 抵抗 10 communication unit 12 transmission control circuit 20 communication line 50A, 50B ... transmission circuit 51 timing circuit 51a inverter 51b timer circuit 51c NAND gate 52 P-type MOS transistor 53 N-type MOS transistor 54 resistance

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 ハイレベル信号およびローレベル信号を
択一的に生成して通信線に出力する送信回路と、前記送
信回路が前記ハイレベル信号またはローレベル信号を出
力するようにその送信回路に制御信号を入力する送信制
御回路とを備えた複数個の通信ユニット間で通信線を介
して信号を授受する通信装置において、 前記送信回路は、前記制御信号が第1のレベルから第2
のレベルに反転するときに所定時間だけタイミング信号
を出力するタイミング回路と、そのタイミング信号に応
答して通信線にハイレベルおよびロ−レベルのいずれか
一方のレベルの信号を出力する第1のトランジスタと、
前記制御信号が前記第2のレベルから第1のレベルに反
転するのに応答して前記通信線に他方のレベルの信号を
出力する第2のトランジスタとを具備することを特徴と
する通信装置。
1. A transmission circuit which selectively generates a high level signal and a low level signal and outputs the high level signal and the low level signal to a communication line, and a transmission circuit which causes the transmission circuit to output the high level signal or the low level signal. In a communication device for transmitting and receiving a signal via a communication line between a plurality of communication units, which comprises a transmission control circuit for inputting a control signal, the transmission circuit is characterized in that the control signal is from a first level to a second level.
Timing circuit for outputting a timing signal for a predetermined time when it is inverted to the level of the above, and a first transistor for outputting a signal of either a high level or a low level to the communication line in response to the timing signal. When,
A second transistor which outputs a signal of the other level to the communication line in response to the control signal being inverted from the second level to the first level.
JP9289492A 1992-04-13 1992-04-13 Communication equipment Pending JPH05292101A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9289492A JPH05292101A (en) 1992-04-13 1992-04-13 Communication equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9289492A JPH05292101A (en) 1992-04-13 1992-04-13 Communication equipment

Publications (1)

Publication Number Publication Date
JPH05292101A true JPH05292101A (en) 1993-11-05

Family

ID=14067172

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9289492A Pending JPH05292101A (en) 1992-04-13 1992-04-13 Communication equipment

Country Status (1)

Country Link
JP (1) JPH05292101A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6301305B1 (en) 1997-06-05 2001-10-09 Honda Giken Kogyo Kabushiki Kaisha Transmitting apparatus for outputting a binary signal

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6301305B1 (en) 1997-06-05 2001-10-09 Honda Giken Kogyo Kabushiki Kaisha Transmitting apparatus for outputting a binary signal

Similar Documents

Publication Publication Date Title
EP0788059B1 (en) Driver circuit device
US5808481A (en) Output swing clamp for USB differential buffer
JPS63209214A (en) Complementary insulating gate inverter
US5237212A (en) Level converting circuit
JPH09121151A (en) Data output buffer
US4963774A (en) Intermediate potential setting circuit
JPH09172367A (en) Level shifter circuit
JPH10209852A (en) Level shifter
JPH05292101A (en) Communication equipment
US5757217A (en) Slow speed driver with controlled slew rate
JPH0766669B2 (en) Decoder buffer circuit
JPH0457020B2 (en)
JPH05152936A (en) Logic circuit
JPH05122049A (en) Output buffer circuit
JP3727440B2 (en) Transmitter
JPH01137821A (en) Cmos output buffer
JPH09205358A (en) Output circuit
JPH0128543B2 (en)
JPH0254615A (en) Output buffer circuit
JPH05145385A (en) Cmos output buffer circuit
JP3623175B2 (en) Signal transmission circuit
JP2001177581A (en) Signal transmission circuit and semiconductor integrated circuit device
JPS63215220A (en) Pre-driver circuit
JPH09205356A (en) Output circuit
JP2595074B2 (en) Semiconductor integrated circuit device