JPH04299035A - Electronic equipment - Google Patents

Electronic equipment

Info

Publication number
JPH04299035A
JPH04299035A JP3061769A JP6176991A JPH04299035A JP H04299035 A JPH04299035 A JP H04299035A JP 3061769 A JP3061769 A JP 3061769A JP 6176991 A JP6176991 A JP 6176991A JP H04299035 A JPH04299035 A JP H04299035A
Authority
JP
Japan
Prior art keywords
main body
power
backup
diode
voltage
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
JP3061769A
Other languages
Japanese (ja)
Inventor
Akitomo Fukui
章智 福井
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Priority to JP3061769A priority Critical patent/JPH04299035A/en
Publication of JPH04299035A publication Critical patent/JPH04299035A/en
Pending legal-status Critical Current

Links

Landscapes

  • Power Sources (AREA)
  • Stand-By Power Supply Arrangements (AREA)
  • Direct Current Feeding And Distribution (AREA)

Abstract

PURPOSE:To provide an electronic equipment in which a life of a battery in a backup state is increased and a circuit element is stably operated by reducing a difference between an operating voltage and a signal voltage. CONSTITUTION:In an electronic equipment in which an external circuit unit containing a backup power source is connected to an equipment body to receive an operating power and a control signal from the body, the unit is so connected that the power to be supplied from the body is received through a diode and a control signal output from the body by an open connector or an open drain connection is received.

Description

【発明の詳細な説明】[Detailed description of the invention]

【0001】0001

【産業上の利用分野】本発明はバックアップ電源が内蔵
された外部回路装置を機器本体に接続して、動作用電源
及び制御信号の供給を受けるようにした電子機器に関す
るものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device in which an external circuit device with a built-in backup power source is connected to the main body of the device to receive operating power and control signals.

【0002】0002

【従来の技術】バックアップ電源が内蔵された外部回路
装置を機器本体に接続して、動作用電源及び制御信号の
供給を受けるようにした電子機器においては、機器本体
から供給された動作用の電源供給部に何らかのスイッチ
が必要であり、さらに、電流の向きを決める必要がある
。これを、従来の回路ではトランジスタスイッチとツェ
ナーダイオードで行っていたものが多い。これを図2で
説明する。
[Prior Art] In electronic equipment in which an external circuit device with a built-in backup power supply is connected to the main body of the device to receive power for operation and control signals, the power supply for operation supplied from the main body of the device is Some kind of switch is required in the supply, and it is also necessary to determine the direction of the current. Most conventional circuits do this using transistor switches and Zener diodes. This will be explained with reference to FIG.

【0003】図2に示す従来の回路では、バックアップ
状態において、ツェナーダイオードに暗電流が流れ、ト
ランジスタが逆向きに動作してしまうことによる大きな
リーク(漏れ)電流があった。まず、電圧5Vの主電源
10が働いている時はPNPトランジスタ15のベース
に接続された抵抗16及びツェナーダイオード17のベ
ース電流が流れ、PNPトランジスタ15が動作してR
TC(Real  TimeClock)電源ライン1
3より動作電圧が供給される。次に、バックアップ時で
は、電圧5Vの主電源10がグランドにつながった状態
となり、バックアップ用の電池14からダイオード12
を介して電源ライン13に電圧3Vが印加される。この
時、トランジスタ15のコレクタ・ベース間に電池14
からの電圧が印加されてベース電流が僅か乍ら流れ、本
体側の電源ライン10にリーク電流が流れる。この無駄
な電力消費が電池の寿命を縮めていた。この問題点を解
決するため、リーク電流の少ないダイオードを用いて電
源供給部のスイッチにすると、ダイオードによる電位降
下が0.6V程現れ、本体からの供給電位V1よりも前
記ユニット上のRTCの動作電位V2が低くなる。つま
り、電位V2よりも入力端子25の信号のHi電位の方
が高くなり、RTCの動作が保証できない。
In the conventional circuit shown in FIG. 2, in the backup state, a dark current flows through the Zener diode, causing the transistor to operate in the opposite direction, resulting in a large leakage current. First, when the main power supply 10 with a voltage of 5V is working, the base current of the resistor 16 and the Zener diode 17 connected to the base of the PNP transistor 15 flows, and the PNP transistor 15 operates and the R
TC (Real Time Clock) power line 1
The operating voltage is supplied from 3. Next, during backup, the main power supply 10 with a voltage of 5V is connected to the ground, and the diode 12 is connected to the backup battery 14.
A voltage of 3V is applied to the power supply line 13 via. At this time, the battery 14 is connected between the collector and base of the transistor 15.
A voltage is applied to the base current, a small amount of base current flows, and a leakage current flows to the power supply line 10 on the main body side. This wasteful power consumption shortened battery life. In order to solve this problem, if a diode with low leakage current is used as a switch in the power supply section, a potential drop due to the diode will appear by about 0.6V, and the operation of the RTC on the unit will be lower than the supply potential V1 from the main unit. Potential V2 becomes low. In other words, the Hi potential of the signal at the input terminal 25 is higher than the potential V2, and the operation of the RTC cannot be guaranteed.

【0004】0004

【発明が解決しようとする課題】外部回路装置のバック
アップ電源から機器本体側の電源ラインに対してリーク
電流が流れることにより、該バックアップ電源である電
池の寿命を縮めることが解決すべき課題1である。次に
、その課題1を解決しようとしてリーク電流の少ないツ
ェナーダイオードを用いると、トランジスタ素子の動作
が保証できなくなる。これが解決すべき課題2である。
[Problem to be Solved by the Invention] Problem 1 to be solved is that leakage current flows from the backup power source of the external circuit device to the power line of the device main body, which shortens the life of the battery that is the backup power source. be. Next, if a Zener diode with low leakage current is used in an attempt to solve Problem 1, the operation of the transistor element cannot be guaranteed. This is problem 2 to be solved.

【0005】[0005]

【課題を解決するための手段】本発明では、バックアッ
プ電源が内蔵された外部回路装置を機器本体に接続して
該機器本体から動作用電源及び制御信号の供給を受ける
電子機器において、前記機器本体から供給される動作用
電源がダイオード素子を介して受け入れられると共に、
該機器本体からオープンコレクタまたはオープンドレイ
ン接続で出力された制御信号を受け入れられるように前
記外部回路装置を接続した構成を有するものである。
[Means for Solving the Problems] The present invention provides an electronic device in which an external circuit device with a built-in backup power source is connected to the device main body to receive operating power and control signals from the device main body. The operating power supplied from is received through the diode element, and
The device has a configuration in which the external circuit device is connected so as to receive a control signal outputted from the main body of the device through an open collector or open drain connection.

【0006】[0006]

【作用】前述の構成により動作電圧と信号電圧の差を小
さくしてバックアップ状態での省電力化を実現すること
ができた。
[Operation] With the above-described configuration, it is possible to reduce the difference between the operating voltage and the signal voltage, thereby realizing power saving in the backup state.

【0007】つまり、前述したRTCの動作、非動作状
態を示すリセット信号に連動する電位V2を作り、これ
に入力端子25の信号をオープンコレクタ、またはオー
プンドレインとして接続することによって前記課題2を
解決し、同時に課題1も解決したものである。
That is, problem 2 is solved by creating a potential V2 that is linked to the reset signal indicating the operation and non-operation state of the RTC mentioned above, and connecting the signal at the input terminal 25 to this as an open collector or open drain. At the same time, issue 1 was also resolved.

【0008】[0008]

【実施例】図1では、RTCにおける本発明の実施例を
示す。
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention in an RTC.

【0009】本体から電圧5Vの主電源10が働いてい
る時はRTCに、ダイオード11を介し、0.6V電圧
降下した4.4Vが電源ライン13より供給される。
When the main power supply 10 with a voltage of 5V is operating from the main body, 4.4V, which is a voltage drop of 0.6V, is supplied to the RTC from the power supply line 13 via the diode 11.

【0010】RESET信号20がHiによりRTCは
動作する。スイッチングトランジスタ21はRESET
信号20がHiのとき動作し、入力信号線23の信号を
有効とし、RESET信号20がLoのとき動作せず、
RTC非動作時には入力信号線23の信号をすべて無効
とする。この状態で、FET24によりオープンドレイ
ン接続されている入力信号線23がLoの信号を出すと
、トランジスタ21のエミッタから抵抗22を介し、4
.4Vに直されたHi電位を入力端子25へ入力する。 従って、RTCの動作電圧より入力信号電圧が高すぎる
という問題がなくなる(課題2が解決)。
[0010] When the RESET signal 20 is Hi, the RTC operates. Switching transistor 21 is RESET
It operates when the signal 20 is Hi, makes the signal on the input signal line 23 valid, and does not operate when the RESET signal 20 is Lo.
When the RTC is not operating, all signals on the input signal line 23 are invalidated. In this state, when the input signal line 23 connected to the open drain by the FET 24 outputs a Lo signal, the 4
.. The Hi potential corrected to 4V is input to the input terminal 25. Therefore, the problem that the input signal voltage is too high than the operating voltage of the RTC is eliminated (Problem 2 is solved).

【0011】次に、本体からの電圧5Vの電源供給が止
まり、ユニットの電池14によるバックアップ状態にな
ると、電圧5Vの主電源ライン10はグランドに継がり
、電圧3Vのバックアップ用電池14からダイオード1
2を介してRTCの電源ライン13へ電力が供給される
。この時、ダイオード11は電池14から逆方向電圧を
受ける。しかし、リーク電流はダイオードなので非常に
小さく、バックアップ状態での消費電力を少なくできる
Next, when the 5V power supply from the main unit is stopped and the unit enters a backup state with the battery 14, the 5V main power line 10 is connected to the ground, and the diode 1 is connected from the 3V backup battery 14.
Power is supplied to the power supply line 13 of the RTC via 2. At this time, diode 11 receives reverse voltage from battery 14. However, since the leakage current is a diode, the leakage current is very small, and power consumption in the backup state can be reduced.

【0012】0012

【発明の効果】以上のように、本発明では、ユニットの
電源切替部にダイオードのみを使用し、信号線の接続部
にオープンコレクタまたはオープンドレイン接続を使用
したことによってユニットの電池の低消費電力化を実現
した。
As described above, in the present invention, the power consumption of the battery of the unit can be reduced by using only a diode in the power supply switching part of the unit and using an open collector or open drain connection in the connection part of the signal line. realized.

【0013】また、消費電力が減った分を電池の小型化
にふり向けて軽量化することもできる。
[0013] Furthermore, the reduced power consumption can be used to reduce the size of the battery, thereby reducing its weight.

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

【図1】本発明の電子機器に係る回路である。FIG. 1 is a circuit related to an electronic device of the present invention.

【図2】従来の電子機器の回路図である。FIG. 2 is a circuit diagram of a conventional electronic device.

【符号の説明】[Explanation of symbols]

10  主電源ライン 11,12  ダイオード素子 13  電源ライン 14  バックアップ用電池 21  トランジスタ素子 22  抵抗素子 23  入力信号線 24  FET素子 10 Main power line 11, 12 Diode element 13 Power line 14 Backup battery 21 Transistor element 22 Resistance element 23 Input signal line 24 FET element

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】  バックアップ電源が内蔵された外部回
路装置を機器本体に接続して該機器本体から動作用電源
及び制御信号の供給を受ける電子機器において、前記機
器本体から供給される動作用電源がダイオード素子を介
して受け入れられると共に、該機器本体からオープンコ
レクタまたはオープンドレイン接続で出力された制御信
号を受け入れられるように前記外部回路装置を接続した
ことを特徴とする電気機器。
1. An electronic device in which an external circuit device with a built-in backup power source is connected to the device main body and receives operating power and control signals from the device main body, wherein the operating power supplied from the device main body is An electrical device, characterized in that the external circuit device is connected so as to be received via a diode element and to receive a control signal output from the device main body through an open collector or open drain connection.
JP3061769A 1991-03-26 1991-03-26 Electronic equipment Pending JPH04299035A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3061769A JPH04299035A (en) 1991-03-26 1991-03-26 Electronic equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3061769A JPH04299035A (en) 1991-03-26 1991-03-26 Electronic equipment

Publications (1)

Publication Number Publication Date
JPH04299035A true JPH04299035A (en) 1992-10-22

Family

ID=13180649

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3061769A Pending JPH04299035A (en) 1991-03-26 1991-03-26 Electronic equipment

Country Status (1)

Country Link
JP (1) JPH04299035A (en)

Similar Documents

Publication Publication Date Title
US4754160A (en) Power supply switching circuit
TR24253A (en) CIRCUIT FOR A REQUESTED VEGETABLE FOR FREE CALISAN BLOCKER OSSILATOER TYPE D
US6873062B1 (en) Switch circuit
DE69306185D1 (en) Stand-by supply circuit
US20090195234A1 (en) On-chip voltage supply scheme with automatic transition into low-power mode of msp430
JPH04299035A (en) Electronic equipment
JP2002093264A (en) Contact damage preventing circuit
US4403309A (en) Automatic back-up circuit
CN114138094B (en) High-reliability on-chip power supply switching circuit
CN210609102U (en) Startup and shutdown circuit
CN215870794U (en) Power supply control circuit and electronic equipment
JP2508085B2 (en) IC card
CN212063619U (en) Relay power supply switching circuit based on photoelectric coupling
KR910008724Y1 (en) Control circuit for chip select of real time clock
JP3542836B2 (en) Power supply circuit for electronic equipment
JPH04372523A (en) Power changeover circuit
JPH0479762A (en) Stabilizing circuit for dc power
CN117792013A (en) Zero standby circuit and driving chip
JPS61246820A (en) Electronic appliance
KR200148401Y1 (en) Power supply device of electronic door lock
JPS6348133A (en) Electric source circuit for memory backup
JPS629744Y2 (en)
JPH11168372A (en) Power switch circuit
JP2000125364A (en) Power supply circuit
KR19990001548U (en) Electronic control unit