JPH0128407B2 - - Google Patents
Info
- Publication number
- JPH0128407B2 JPH0128407B2 JP56195932A JP19593281A JPH0128407B2 JP H0128407 B2 JPH0128407 B2 JP H0128407B2 JP 56195932 A JP56195932 A JP 56195932A JP 19593281 A JP19593281 A JP 19593281A JP H0128407 B2 JPH0128407 B2 JP H0128407B2
- Authority
- JP
- Japan
- Prior art keywords
- load circuit
- switching transistor
- voltage
- power supply
- switching
- 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
- 230000007423 decrease Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000009429 electrical wiring Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
- H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
- H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
- H02J9/061—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems for DC powered loads
Landscapes
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Power Sources (AREA)
- Stand-By Power Supply Arrangements (AREA)
- Direct Current Feeding And Distribution (AREA)
Description
【発明の詳細な説明】
本発明は主電源の他に補助電源を有する電源回
路に係り、補助電源が不用意に必要以上に消費さ
れるのを極力防止できる優れた電源回路を提供す
ることを目的とするものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power supply circuit having an auxiliary power supply in addition to the main power supply, and an object of the present invention is to provide an excellent power supply circuit that can prevent the auxiliary power supply from being inadvertently consumed more than necessary. This is the purpose.
一般にマイクロコンピユータ等を内蔵した機器
等においては主電源用の電池等を交換する際にマ
イクロコンピユータ等に記憶された情報が消滅し
ないようにするために、別に補助電源を設けてお
く必要がある。したがつて、従来よりこの種の機
器に使用する電源回路は第１図に示すように構成
することが多い。第１図において、１は主電源用
の電池、２，３は定電圧回路を構成する抵抗及び
定電圧ダイオード、４，５はスイツチング用ダイ
オード、６は補助電源用の電池、７は抵抗、８は
マイクロコンピユータ等の負荷回路、９は負荷回
路８の動作を動作状態、保持状態に切換える切換
スイツチである。 Generally, in devices with a built-in microcomputer, etc., it is necessary to provide a separate auxiliary power source in order to prevent the information stored in the microcomputer from disappearing when replacing the main power source battery. Therefore, conventionally, power supply circuits used in this type of equipment have often been configured as shown in FIG. In Figure 1, 1 is a battery for the main power supply, 2 and 3 are resistors and constant voltage diodes that constitute a constant voltage circuit, 4 and 5 are switching diodes, 6 is a battery for auxiliary power supply, 7 is a resistor, and 8 9 is a load circuit such as a microcomputer, and 9 is a changeover switch for switching the operation of the load circuit 8 between an operating state and a holding state.
第１図に示す従来の電源回路において主電源用
の電池１が充分な電源供給能力を有する場合には
定電圧ダイオード３によつて抵抗２と定電圧ダイ
オード３との接続点に一定の電圧が現われダイオ
ード４がオンし、上記一定の電圧が負荷回路８に
印加される。主電源用の電池１が電源供給能力を
有しないようになつたり、そのために主電源用の
電池を取除いた場合にはダイオード５がオンし補
助電源用の電池６から負荷回路８に所定の電圧が
印加される。 In the conventional power supply circuit shown in FIG. 1, if the main power supply battery 1 has sufficient power supply capacity, a constant voltage is applied to the connection point between the resistor 2 and the voltage regulator diode 3 by the voltage regulator diode 3. Then, the diode 4 is turned on, and the above-mentioned constant voltage is applied to the load circuit 8. When the main power battery 1 no longer has the power supply capability or if the main power battery is removed, the diode 5 turns on and the auxiliary power battery 6 connects the load circuit 8 to a specified level. A voltage is applied.
ところで、この場合、従来の電源回路では切換
スイツチ９のオン、オフ状態すなわち負荷回路８
の動作状態、保持状態に関係なく、補助電源用電
池６から負荷回路８に電源が供給されるため、誤
まつて切換スイツチ９をオフ状態にし、負荷回路
８を動作状態にした状態で主電源用の電池１を取
除くと補助電源用電池６の消耗が著しく早くなり
負荷回路８に記憶された情報が誤まつて消滅して
しまうことがあるなどきわめて不都合なものであ
つた。 By the way, in this case, in the conventional power supply circuit, the on/off state of the changeover switch 9, that is, the load circuit 8
Since power is supplied from the auxiliary power battery 6 to the load circuit 8 regardless of the operating state or holding state of the If the secondary battery 1 is removed, the auxiliary power battery 6 will wear out extremely quickly, and the information stored in the load circuit 8 may be erroneously erased, which is extremely inconvenient.
本発明は以上のような従来の欠点を除去するも
のであり、主電源から補助電源に切換えられる際
には、その以前に強制的に負荷回路が保持状態に
切換えられるように構成したものである。 The present invention eliminates the above-mentioned conventional drawbacks, and is configured such that the load circuit is forcibly switched to the holding state before switching from the main power source to the auxiliary power source. .
以下、本発明の電源回路について一実施例の図
面とともに説明する。第２図は本発明の電源回路
における一実施例の電気的結線図であり、図中、
Bnは主電源用電池、Bbは補助電源用電池、R1〜
R9は抵抗、TR1〜TR5はそれぞれトランジスタ、
Dz，D3は定電圧ダイオード、D1，D2はスイツチ
ング用ダイオード、SWは負荷回路Ｌの動作状
態、保持状態切換用スイツチである。 DESCRIPTION OF THE PREFERRED EMBODIMENTS A power supply circuit according to the present invention will be described below with reference to drawings of an embodiment. FIG. 2 is an electrical connection diagram of one embodiment of the power supply circuit of the present invention, and in the figure,
B n is the main power battery, B b is the auxiliary power battery, R 1 ~
R 9 is a resistor, TR 1 to TR 5 are each a transistor,
D z and D 3 are constant voltage diodes, D 1 and D 2 are switching diodes, and SW is a switch for changing the operating state and holding state of the load circuit L.
上記実施例において主電源用の電池Bnが充分
電源供給能力を有する場合には抵抗R1と定電圧
ダイオードDzとの接続点に定電圧ダイオードDz
によつて決定される一定の電圧Vnが現われ、こ
れがダイオードD1を介して負荷回路Ｌの電源端
子Vddに印加される。そして、この場合にはトラ
ンジスタTR1，TR2のベース電位も所定の値を維
持しており、第１、第２、第３、第４のトランジ
スタTR1，TR2，TR3，TR4が共にオンの状態に
ある。したがつて、第５のトランジスタTR5はオ
フの状態にあり、補助電源用電池Bbは完全に切
離されている。そして、第３のトランジスタTR3
がオンの状態にあることから、スイツチSWがオ
フの状態では負荷回路Ｌが動作状態になり、オン
した場合には保持状態に切換えられる。 In the above embodiment, if the battery B n for the main power supply has sufficient power supply capacity, a voltage regulator diode D z is connected to the connection point between the resistor R 1 and the voltage regulator diode D z .
A constant voltage V n determined by V n appears, which is applied via the diode D 1 to the power supply terminal V dd of the load circuit L. In this case, the base potentials of the transistors TR 1 and TR 2 are also maintained at a predetermined value, and the first, second, third, and fourth transistors TR 1 , TR 2 , TR 3 , and TR 4 are Both are in the on state. Therefore, the fifth transistor TR 5 is in an off state, and the auxiliary power supply battery B b is completely disconnected. and a third transistor TR 3
Since the switch SW is in the on state, the load circuit L is in the operating state when the switch SW is off, and is switched to the holding state when the switch SW is on.
今、主電源用電池Bnの電圧がある定められた
第１の一定電圧すなわち定電圧ダイオードDzの
ツエナー電圧より低下したとする。この場合には
抵抗R1と定電圧ダイオードDzとの接続点におけ
る電位Vnが同様に低下するため、トランジスタ
TR1，TR2のベース電位も同様に低下する。した
がつて先ず、第１のトランジスタTR1がオフし、
第３のトランジスタTR3がオフする。そのため、
スイツチSWのオン、オフ状態に関係なく負荷回
路Ｌの動作状態、保持状態切換用端子Run／
Holdのレベルがローレベルになり、実質的にス
イツチSWがオンされたと同じ状態になる。すな
わち、この状態では先ず負荷回路Ｌが強制的に保
持状態になり、負荷回路Ｌによる電力消費が少な
くなるように切換えられる。そして、更に主電源
用電池Bnの電圧が低下し抵抗R1と定電圧ダイオ
ードDzとの接続点における電位Vnが予め定めら
れた第２の一定電圧より低下したとすると、この
時点でトランジスタTR2がオフし、トランジスタ
TR4がオフすることになる。したがつて、この状
態では第５のトランジスタTR5がオンし、補助電
源用電池Bnの電圧が第５のトランジスタTR5を
介して負荷回路Ｌの電源端子Vddに印加されるこ
とになる。 Suppose that the voltage of the main power supply battery B n has decreased below a certain first constant voltage, that is, the Zener voltage of the voltage regulator diode D z . In this case, the potential V n at the connection point between the resistor R 1 and the voltage regulator diode D z similarly decreases, so the transistor
The base potentials of TR 1 and TR 2 similarly decrease. Therefore, first, the first transistor TR1 is turned off,
The third transistor TR3 is turned off. Therefore,
Regardless of the on/off state of the switch SW, the operating state of the load circuit L and the holding state switching terminal Run/
The Hold level becomes low level, which is essentially the same state as when the switch SW was turned on. That is, in this state, first, the load circuit L is forcibly put into the holding state and switched so that the power consumption by the load circuit L is reduced. If the voltage of the main power supply battery B n further decreases and the potential V n at the connection point between the resistor R 1 and the voltage regulator diode D z falls below a predetermined second constant voltage, at this point Transistor TR 2 turns off, transistor
TR 4 will turn off. Therefore, in this state, the fifth transistor TR5 is turned on, and the voltage of the auxiliary power supply battery Bn is applied to the power supply terminal Vdd of the load circuit L via the fifth transistor TR5 . .
このように上記実施例によれば主電源用電池
Bnの電圧がある定められた第１の一定電圧以下
に低下すると、先ず負荷回路Ｌが強制的に保持状
態になり、負荷回路Ｌによる電力消費が少なくな
るように作用する。そして、更に主電源用電池
Bnの電圧がある定められた第２の一定電圧以下
に低下すると、その時点で初めて補助電源用電池
Bbの電圧が負荷回路Ｌに印加されることになり、
補助電源用電池Bbの消耗が著しく少なくなる。 In this way, according to the above embodiment, the main power battery
When the voltage of B n falls below a predetermined first constant voltage, the load circuit L is first forced into a holding state, and the power consumption by the load circuit L is reduced. And then the main power battery
When the voltage of B n drops below a predetermined second constant voltage, the auxiliary power battery is used for the first time.
A voltage of B b will be applied to the load circuit L,
The consumption of the auxiliary power battery B b is significantly reduced.
ここで、本実施例を具体数値例をもつて説明す
るならば、定電圧ダイオードDzのツエナー電圧
を3V、補助電源用電池Bbの電圧を3V、TR1〜
TR5が共にシリコントランジスタ、D2がシリコ
ンダイオード、D1がゲルマニウムダイオード、
定電圧ダイオードD3のツエナー電圧を1.6Vとす
れば、主電源用電池Bnの電源供給能力が充分あ
る状態ではVn＝3V、従つてVn―Vy＝1.4Vであ
るので、トランジスタTR1，TR2は共にオン状態
にあり、トランジスタTR4もオン状態であつてト
ランジスタTR5はオフ状態である。 Here, to explain this embodiment using a specific numerical example, the Zener voltage of the constant voltage diode D z is 3V, the voltage of the auxiliary power battery B b is 3V, and TR 1 ~
Both TR 5 is a silicon transistor, D 2 is a silicon diode, D 1 is a germanium diode,
If the Zener voltage of the voltage regulator diode D3 is 1.6V, when the main power supply battery Bn has sufficient power supply capacity, Vn = 3V, and therefore Vn - Vy = 1.4V, so the transistor Both TR 1 and TR 2 are in an on state, transistor TR 4 is also in an on state, and transistor TR 5 is in an off state.
故に、補助電源用電池Bbからの電源供給はな
されず、負荷回路ＬのVddはVnよりダイオード
D1の電圧降下分だけ低い約2.9Vが主電源用電池
Bnから供給される。一方、トランジスタTR3も
オン状態にあるので、負荷回路ＬのRum／Halt
端子はスイツチSWの状態に応じてハイレベル又
はローレベルとなり、動作状態と保持状態を実現
する。 Therefore, power is not supplied from the auxiliary power battery B b , and V dd of the load circuit L is connected to the diode rather than V n.
Approximately 2.9V, which is lower by the voltage drop of D 1 , is the main power battery.
Supplied by B n . On the other hand, since transistor TR3 is also in the on state, Rum/Halt of load circuit L
The terminal becomes high level or low level depending on the state of the switch SW, and realizes the operating state and the holding state.
トランジスタTR1，TR2のスレツシユホールド
電圧はいずれも0.6Vとして、主電源用電池Bnの
供給能力が低下し、Vn＜2.8Vとなると、Vn―Vy
＜1.2V，Vn―Vx＜0.6V、従つて、トランジスタ
TR1のみオフ状態となつてトランジスタTR3がオ
フ状態となり、スイツチSWの状態如何にかかわ
らず負荷回路ＬのRun／Halt端子はローレベル
となるので、負荷回路ＬはVddに主電源用電池Bn
から約2.47Vが供給されて保持状態となる。 The threshold voltages of transistors TR 1 and TR 2 are both 0.6V, and when the supply capacity of the main power supply battery B n decreases and V n < 2.8V, V n −V y
<1.2V, V n −V x <0.6V, therefore the transistor
Only TR 1 is turned off, transistor TR 3 is turned off, and the Run/Halt terminal of load circuit L is at low level regardless of the state of switch SW, so load circuit L is connected to V dd from the main power battery. B n
Approximately 2.47V is supplied from the voltage and the state is maintained.
更に、Vn＜2.2Vとなると、Vn―Vy＜0.6V、従
つて、トランジスタTR2がオフ状態になつてトラ
ンジスタTR4がオフ状態になり、トランジスタ
TR5がオン状態となり、補助電源用電池Bbから
負荷回路ＬのVddへ約2.9Vが供給され、負荷回路
Ｌは保持状態を保つ。 Furthermore, when V n <2.2V, V n −V y <0.6V, therefore, transistor TR 2 is turned off, transistor TR 4 is turned off, and the transistor
TR 5 is turned on, approximately 2.9V is supplied from the auxiliary power supply battery B b to V dd of the load circuit L, and the load circuit L maintains the holding state.
以上のように本発明は、主電源と補助電源とを
有し、主電源の電圧が第１の一定電圧以下になつ
たとき動作する第１のスイツチングトランジスタ
に応動して作動される第３のスイツチングトラン
ジスタによつて、マイクロコンピユータ等の負荷
回路の動作状態と保持状態とを切換えるための制
御電圧が印加される切換え制御端子と接地間に挿
入した切換スイツチを無効化し、かつ上記第２の
スイツチングトランジスタによつて上記切換え制
御端子に上記負荷回路を強制的に保持状態にする
ための制御電圧を印加し、上記第１の一定電圧よ
り低い第２の一定電圧になつたとき動作する第２
のスイツチングトランジスタに応動して作動され
る第４のスイツチングトランジスタによつて補助
電源を負荷回路に供給する第５のスイツチングト
ランジスタを制御することによつて上記負荷回路
に補助電源を供給するように構成したものであ
り、補助電源を用いるときには必ず負荷回路を動
作状態と保持状態に切換える切換スイツチを無効
化して負荷回路を強制的に保持状態とすることが
できる。したがつて、上記切換スイツチの切換え
如何にかかわらず補助電源が早期に消費するよう
なことは全くなく、小さな容量の補助電源でも充
分にその役目を果たすことが可能となり、実用上
きわめて有利なものである。また第３、第４のス
イツチングトランジスタは夫々第１、第２のスイ
ツチングトランジスタによりオン、オフ制御する
ため、第３、第４のスイツチングトランジスタの
作動ポイントを任意に設定可能であり、負荷回路
が保持状態になつて以後に確実に補助電源により
負荷回路をバツクアツプすることができるもので
ある。 As described above, the present invention has a main power source and an auxiliary power source, and has a third switching transistor that is activated in response to the first switching transistor that is activated when the voltage of the main power source falls below a first constant voltage. The switching transistor disables the switching switch inserted between the switching control terminal to which a control voltage is applied for switching between the operating state and the holding state of a load circuit such as a microcomputer, and the ground, and the above-mentioned second switching transistor. A control voltage for forcibly bringing the load circuit into a holding state is applied to the switching control terminal by the switching transistor, and the circuit operates when a second constant voltage lower than the first constant voltage is reached. Second
supplying auxiliary power to the load circuit by controlling a fifth switching transistor which supplies auxiliary power to the load circuit by a fourth switching transistor activated in response to the switching transistor; With this structure, whenever the auxiliary power source is used, the changeover switch that switches the load circuit between the operating state and the holding state can be disabled and the load circuit can be forced into the holding state. Therefore, regardless of whether the above-mentioned changeover switch is switched, the auxiliary power supply will not be consumed prematurely, and even a small capacity auxiliary power supply can sufficiently fulfill its role, which is extremely advantageous in practical terms. It is. Furthermore, since the third and fourth switching transistors are controlled on and off by the first and second switching transistors, respectively, the operating points of the third and fourth switching transistors can be set arbitrarily, and the load After the circuit enters the holding state, the load circuit can be reliably backed up by the auxiliary power source.
第１図は従来の電源回路の電気的結線図、第２
図は本発明の電源回路の一実施例の電気的結線図
である。
Bn……主電源用電池、R1〜R9……抵抗、Dz，
D3……定電圧ダイオード、TR1〜TR5……トラ
ンジスタ、D1〜D2……ダイオード、Ｌ……負荷
回路、SW……動作状態、保持状態切換用スイツ
チ、Bb……補助電源用電池。
Figure 1 is an electrical wiring diagram of a conventional power supply circuit;
The figure is an electrical wiring diagram of one embodiment of the power supply circuit of the present invention. B n ...Battery for main power supply, R1 to R9 ...Resistance, Dz ,
D 3 ... Constant voltage diode, TR 1 - TR 5 ... Transistor, D 1 - D 2 ... Diode, L ... Load circuit, SW ... Operating state, holding state switching switch, B b ... Auxiliary power supply battery.
Claims (1)
たときオフする第１のスイツチングトランジスタ
と、主電源の電圧が上記第１の一定電圧より低い
第２の一定電圧以下に低下したときオフする第２
のスイツチングトランジスタと、マイクロコンピ
ユータ等の負荷回路の動作状態と保持状態とを切
換えるための制御電圧が印加される切換え制御端
子と上記主電源の間に挿入され、通常オン状態に
あつて上記切換え制御端子に上記負荷回路を動作
状態とするための制御電圧を印加するも、上記第
１のスイツチングトランジスタのオフ動作に応動
してオフされて上記切換え制御端子に上記負荷回
路を動作状態から強制的に保持状態とするための
制御電圧を印加すると共に上記切換え制御端子と
接地間に挿入した切換スイツチを無効化する第３
のスイツチングトランジスタと、上記負荷回路と
補助電源との間に接続され、上記負荷回路に上記
補助電源を供給する第５のスイツチングトランジ
スタと、この第５のスイツチングトランジスタの
制御端子と上記主電源間に接続され、通常オン状
態にあつて上記補助電源を上記負荷回路から切離
すように上記第５のスイツチングトランジスタを
制御するも上記第２のスイツチングトランジスタ
のオフ動作に応動してオフされた時に上記補助電
源より上記負荷回路に電源供給されるように上記
第５のスイツチングトランジスタを制御する第４
のスツチングトランジスタとを備えたことを特徴
とする電源回路。1 A first switching transistor that turns off when the voltage of the main power source drops below a first constant voltage, and a first switching transistor that turns off when the voltage of the main power source drops below a second constant voltage that is lower than the first constant voltage. Second to do
The switching transistor is inserted between the switching control terminal to which a control voltage is applied for switching between the operating state and the holding state of a load circuit such as a microcomputer, and the above-mentioned main power supply. Although a control voltage is applied to the control terminal to bring the load circuit into the operating state, it is turned off in response to the off operation of the first switching transistor, forcing the load circuit from the operating state to the switching control terminal. A third switch that applies a control voltage to maintain the hold state and disables the switch inserted between the switch control terminal and ground.
a fifth switching transistor connected between the load circuit and the auxiliary power source and supplying the auxiliary power source to the load circuit; and a fifth switching transistor connected between the control terminal of the fifth switching transistor and the main power source. The fifth switching transistor is connected between the power supplies, and controls the fifth switching transistor so as to disconnect the auxiliary power supply from the load circuit when it is normally on, but is turned off in response to the off operation of the second switching transistor. a fourth switching transistor that controls the fifth switching transistor so that power is supplied to the load circuit from the auxiliary power source when
A power supply circuit characterized in that it is equipped with a switching transistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56195932A JPS5897719A (en) | 1981-12-04 | 1981-12-04 | Power supply circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP56195932A JPS5897719A (en) | 1981-12-04 | 1981-12-04 | Power supply circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5897719A JPS5897719A (en) | 1983-06-10 |
| JPH0128407B2 true JPH0128407B2 (en) | 1989-06-02 |
Family
ID=16349366
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP56195932A Granted JPS5897719A (en) | 1981-12-04 | 1981-12-04 | Power supply circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5897719A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62134136U (en) * | 1986-02-17 | 1987-08-24 | ||
| JPS63245705A (en) * | 1987-04-01 | 1988-10-12 | Japan Electronic Control Syst Co Ltd | Memory backup device for ic |
-
1981
- 1981-12-04 JP JP56195932A patent/JPS5897719A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5897719A (en) | 1983-06-10 |
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