EP0307325A1 - Steuerungskreis für eine Zündung - Google Patents

Steuerungskreis für eine Zündung Download PDF

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Publication number
EP0307325A1
EP0307325A1 EP88420284A EP88420284A EP0307325A1 EP 0307325 A1 EP0307325 A1 EP 0307325A1 EP 88420284 A EP88420284 A EP 88420284A EP 88420284 A EP88420284 A EP 88420284A EP 0307325 A1 EP0307325 A1 EP 0307325A1
Authority
EP
European Patent Office
Prior art keywords
amplifier
current
comparator
voltage
transistor
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
Application number
EP88420284A
Other languages
English (en)
French (fr)
Other versions
EP0307325B1 (de
Inventor
Jean-Michel Moreau
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.)
STMicroelectronics SA
Original Assignee
SGS Thomson Microelectronics SA
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 SGS Thomson Microelectronics SA filed Critical SGS Thomson Microelectronics SA
Publication of EP0307325A1 publication Critical patent/EP0307325A1/de
Application granted granted Critical
Publication of EP0307325B1 publication Critical patent/EP0307325B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
    • F02P3/00—Other installations
    • F02P3/02—Other installations having inductive energy storage, e.g. arrangements of induction coils
    • F02P3/04—Layout of circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
    • F02P3/00—Other installations
    • F02P3/02—Other installations having inductive energy storage, e.g. arrangements of induction coils
    • F02P3/04—Layout of circuits
    • F02P3/05—Layout of circuits for control of the magnitude of the current in the ignition coil
    • F02P3/051—Opening or closing the primary coil circuit with semiconductor devices

Definitions

  • the present invention relates to an ignition control circuit and in particular a so-called electronic control circuit for motor vehicles in which the spark of a spark plug is obtained at the secondary of a voltage-raising coil at the moment when the current passing through the primary of this coil.
  • FIG. 1 represents an example of such a conventional electronic ignition system comprising an energy storage battery 1 (the automobile battery) and a lifting coil 2, the secondary of which is connected to a spark gap 3 and the primary of which is in series with an electronic switch 4, such as an assembly of Darlington transistors, making it possible to let the current pass or interrupt the current in the coil.
  • a control member 5 makes it possible to control, as a function of information received from the motor 6, the closing then the opening of the switch 4, this control member acting on the base of the main switch which, in the example shown, is bipolar.
  • This detection circuit 7 in series with the power switch 4.
  • This detection circuit comprises a resistor R1 of low value in parallel with a divider circuit comprising resistors R2 and R3, the voltage detected at the common point between the resistors R2 and R3 being proportional to the current passing through the resistor R1.
  • This detected voltage V D is compared to a reference voltage 8 in a controlled comparator amplifier 9 whose output supplies a basic current to the power switch 4.
  • the amplifier 9, produced in an integrated circuit is a high gain amplifier, for example with three stages. Current technologies mean that this gain can vary for each stage by a factor of 3, for example between 100 and 300. Similarly, the gain of the power switch 4, which is for example a Darlington assembly with several stages, can vary considerably , for example by a factor of 30. Under these conditions, it is very difficult in practice to ensure a predetermined value for the loop gain of the servo and consequently to ensure the stability of the servo in current.
  • An object of the present invention is to provide an ignition control circuit whose control in the current limitation phase is stable thanks to a predictable loop gain.
  • Another object of the present invention is to provide that this control circuit which is constituted in practice by a specialized integrated circuit can be used in connection with different bipolar Darlington transistors or.
  • an object of the invention is to make the contribution to the loop gain of the amplifier contained in the control member reproducible when the latter is produced in the form of an integrated circuit.
  • Another object of the present invention is to make this contribution externally adjustable so as to be able to compensate for the differences in gain provided by the different types of power members.
  • the present invention provides a control circuit comprising a bipolar power switch in series with the primary of an ignition coil and a detection resistor; a voltage divider in parallel on the detection resistor providing a detected voltage proportional to the current in the resistance; a controlled comparator amplifier, the first input of which receives the detected voltage and the second input of which receives a reference voltage, the output of which is connected to the base of the power switch and the control input of which can receive a general inhibition order, this amplifier-comparator acting to limit the base current when the detected voltage approaches the reference voltage; a series resistor between the output of the comparator amplifier and the base of the power switch; and a differential amplifier whose inputs are connected to the terminals of the series resistor and whose output is connected to the first input of the comparator amplifier.
  • this circuit further comprises means for inhibiting the action of the differential amplifier when the detected voltage is less than a selected threshold at most equal to the reference voltage.
  • the differential amplifier comprises multi-collector transistors whose emitters are connected to the terminals of the series resistor, whose first collectors are interconnected and whose second collectors are connected to active loads consisting of transistors connected in current mirror .
  • the resistors of the voltage divider are adjustable so that their ratio is adjusted to obtain a limitation of the current in the power switch to a predetermined value and that the absolute value of the resistance in series with the input of the amplifier-comparator is chosen to determine the gain of the servo circuit.
  • This amplifier 9 acts on the control terminal of the power switch 4 via a resistor R10 in series.
  • This resistor R10 constitutes a means of measuring the input current into the control terminal, commonly the base, of the bipolar power switch 4.
  • a differential amplifier 11 of transconductance y D (ratio between the variation of output current and the variation of input voltage) has its inputs connected to the terminals of the resistor R10.
  • the output of this differential amplifier 11 is connected to the first input of the amplifier-comparator 9 in a direction such that the loop formed by this amplifier-comparator, the resistor R10 and the differential amplifier 11 performs a feedback.
  • this structure brings the following advantages: - Despite all the variations which may affect the gain of the high gain amplifier-comparator 9, the transconductance between the detection resistor R1 and the control terminal can be maintained well defined provided that R2, R10 and y D are defined .
  • R2, R10 and y D are defined .
  • the transconductance of a differential amplifier is reproducible data.
  • the current gain of the power switch 4 is a cause of dispersion in the overall gain of the current control loop and the stability is easier to control.
  • the coil with its parasitic capacities constitutes an oscillating circuit which is excited for example ple when the power switch 4 switches from the closed switch mode (when a maximum base current is supplied) to the current regulator mode (when we begin to reduce, quite abruptly, the base current of the power switch), this is ie when the voltage across the coil drops suddenly from LdI / dt to a zero value (constant I).
  • the large voltage variation at this time triggers damped oscillations which can disturb other organs connected to the circuit, for example, in automotive applications, the tachometer.
  • the gain of the control loop which tends to transform it into a source of high impedance must not be excessive. According to the invention, this gain can be controlled by adjusting the value of the resistance R2.
  • the adjustment of the potentiometer R2, R3 has a double function: by adjusting R2, the gain of the control loop is fixed, by adjusting the ratio R2 / R3, the desired level of current limitation is fixed in the power switch.
  • a drawback of the circuit according to the present invention as described above could be that, from the initial phase of closing the power switch 4, the differential amplifier 11 begins to act to reduce the base current in this power switch and therefore to slow the rate of current increase in the coil primary.
  • the output of comparator 12 inhibits the operation of the differential amplifier 11 as long as the detected voltage, ie ie the current in the resistor R1, has not reached a certain threshold. It is only from this threshold that the feedback begins to act.
  • FIG. 3 represents a detailed embodiment of certain elements of the circuit shown very schematically in FIG. 2.
  • the amplifier-comparator 9 comprises an amplification chain made up of PNP T57 and NPN T59 and T62 transistors. At its input, there are two NPN transistors T51 and T55 mounted as a comparator, the emitter of transistor T51 being connected to an input terminal E9 which receives the signal V D coming from the connection point of the resistors R2 and R3 mentioned above .
  • the emitter of transistor T55 is connected to a resistor R8 which defines, in relation to a current source I8, the reference voltage represented by the voltage source 8 in FIGS. 1 and 2.
  • the input comparator includes the following connections.
  • the transistor T51 is connected by its collector to a current source I51 whose other terminal is connected to the supply voltage VCC.
  • the emitter of transistor T51 is connected to terminal E9 as indicated above, the base of transistor T51 is connected to its collector and to the base of transistor T55.
  • the collector of transistor T55 is connected to the supply voltage VCC by a current source I8 and its emitter is connected to ground via a resistor R8.
  • the signal at the output terminal 23 of the comparator is connected to the input transistor T57 of the amplifier circuit comprising the transistors T57, T59 and T62.
  • the amplification part includes the following connections.
  • the PNP transistor T57 whose base is connected to the output terminal 23 of the comparator has its transmitter connected to a current source I57 itself connected to the supply voltage VCC.
  • the collector of transistor T57 is connected to ground by a transistor T45 maintained in the on state.
  • the emitter and the collector of transistor T57 are connected to ground via NPN transistors T56 and T60, the role of which will be explained below.
  • the emitter of transistor T57 is also connected to the base of the second NPN-type transistor T59 whose collector is connected to terminal VCC by a current limiting resistor R59 and whose emitter is connected to ground via a transistor T61 whose role will be explained below.
  • the emitter of transistor T59 is also connected to the base of transistor T62 whose collector is connected to terminal VCC by a current limiting resistor R62 and whose emitter is connected to ground via a resistor R61 and to the output terminal S9 of circuit 9.
  • the three transistors T56, T60 and T61 contained in a block 30 constitute the inhibition control circuit of the amplifier 9.
  • This circuit receives a signal from a control input terminal EC9 connected to a processing circuit signal receiving information from the motor 6. It will be seen that the circuit 30 also serves to disable the differential amplifier 11.
  • the differential amplifier 11 has its input terminals connected to the terminals of the resistor R10 and its output terminal A connected to the terminal A indicated in block 9 at the emitter of transistor T51, that is to say tell at terminal E9 where the detected voltage V D is applied.
  • This differential amplifier 11 includes two input resistors R11 and R12 connected to the emitters of PNP transistors with two collectors T63 and T70 mounted in differential, that is to say connected by their bases, and has a constant gain thanks to an interconnection of the second collectors.
  • the first collectors are connected to ground by a load made up of two NPN transistors T76 and T77 connected in current mirror.
  • the collectors of transistors T76 and T77 are respectively connected to the collectors of transistors T63 and T70, their emitters being grounded, their bases being interconnected and the collector and the base of transistor T77 being connected.
  • the signal on the collector of transistor T76 which is the amplified image of the current in the resistor R10, is supplied to the output terminal A, via a transistor T78 mounted as a diode, to provide a feedback. .
  • the control of the transistor T79 is ensured by a circuit comprising, between the voltage VCC and the ground, a resistor R16, a transistor T43 and a resistor R20.
  • the base of transistor T43 is connected to the collector of transistor T45 and the emitter of transistor T43 is connected to the base of transistor T79.
  • the output current of the differential amplifier 11 is available on the collectors of the transistors T63 and T76.
  • the role of transistor T78, connected as a diode, is to allow transistor T76 to operate with a sufficient collector voltage; indeed the terminal E9 always remains at a potential close to that of the ground.
  • the circuit is arranged so that the transistor T79 becomes conductive very shortly before the current in the coil reaches the set value. So : - the gain of the servo remains very high (amplifier 11 off) for almost the entire time of current rise in the coil (period when it is important that the switch 4 receives the maximum base current); - The gain of the control falls to a low value (amplifier 11 in operation) shortly before the set value is reached, thus providing the advantages which have been described.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)
  • Amplifiers (AREA)
  • Electrical Control Of Ignition Timing (AREA)
EP88420284A 1987-08-27 1988-08-23 Steuerungskreis für eine Zündung Expired - Lifetime EP0307325B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8712103A FR2619859B1 (fr) 1987-08-27 1987-08-27 Circuit de commande d'allumage
FR8712103 1987-08-27

Publications (2)

Publication Number Publication Date
EP0307325A1 true EP0307325A1 (de) 1989-03-15
EP0307325B1 EP0307325B1 (de) 1993-03-10

Family

ID=9354524

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88420284A Expired - Lifetime EP0307325B1 (de) 1987-08-27 1988-08-23 Steuerungskreis für eine Zündung

Country Status (7)

Country Link
US (1) US4912373A (de)
EP (1) EP0307325B1 (de)
JP (1) JP2621946B2 (de)
KR (1) KR890004068A (de)
DE (1) DE3879051T2 (de)
ES (1) ES2038781T3 (de)
FR (1) FR2619859B1 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0428315A2 (de) * 1989-11-13 1991-05-22 AT&T GLOBAL INFORMATION SOLUTIONS INTERNATIONAL INC. Stromregelung in einer Zündspule für verteilerlose Zündanlage
EP0639894A1 (de) * 1993-08-18 1995-02-22 Co.Ri.M.Me. Consorzio Per La Ricerca Sulla Microelettronica Nel Mezzogiorno Schaltung zur Begrenzung des Maximalstroms, den ein Leistungstransistor an eine Last liefert
EP0444043B1 (de) * 1988-11-18 1996-03-27 Robert Bosch Gmbh Zündendstufe einer transistor-zündanlage

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2568813Y2 (ja) * 1992-02-19 1998-04-15 三菱電機株式会社 内燃機関用点火装置
US5446385A (en) * 1992-10-02 1995-08-29 Robert Bosch Gmbh Ignition system for internal combustion engines
JP3530714B2 (ja) * 1997-05-26 2004-05-24 株式会社日立製作所 内燃機関用点火装置
DE102004013561B4 (de) * 2004-03-19 2007-02-22 Audi Ag Verfahren und Schaltvorrichtung zum Betreiben einer Zündspule eines Kraftfahrzeugs
DE102008000871B4 (de) * 2008-03-28 2021-07-01 Robert Bosch Gmbh Schaltungsanordnung zum Schalten des Stromflusses durch eine Zündspule
JP5253012B2 (ja) * 2008-06-24 2013-07-31 ローム株式会社 パワー半導体の駆動回路装置およびそれに用いる信号伝達回路装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3838672A (en) * 1973-08-23 1974-10-01 Gen Motors Corp Internal combustion engine ignition system
FR2427713A1 (fr) * 1978-06-02 1979-12-28 Hitachi Ltd Dispositif d'allumage pour moteurs a combustion interne
GB2024941A (en) * 1978-07-07 1980-01-16 Bosch Gmbh Robert Ignition system for an internal combustionengine

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4574221A (en) * 1984-01-04 1986-03-04 Motorola, Inc. Ignition control integrated circuit having substrate injection preventing means

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3838672A (en) * 1973-08-23 1974-10-01 Gen Motors Corp Internal combustion engine ignition system
FR2427713A1 (fr) * 1978-06-02 1979-12-28 Hitachi Ltd Dispositif d'allumage pour moteurs a combustion interne
GB2024941A (en) * 1978-07-07 1980-01-16 Bosch Gmbh Robert Ignition system for an internal combustionengine

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0444043B1 (de) * 1988-11-18 1996-03-27 Robert Bosch Gmbh Zündendstufe einer transistor-zündanlage
EP0428315A2 (de) * 1989-11-13 1991-05-22 AT&T GLOBAL INFORMATION SOLUTIONS INTERNATIONAL INC. Stromregelung in einer Zündspule für verteilerlose Zündanlage
EP0428315A3 (en) * 1989-11-13 1993-06-23 Ncr Corporation Circuit & method for regulating the current flow in a distributorless ignition system coil
EP0639894A1 (de) * 1993-08-18 1995-02-22 Co.Ri.M.Me. Consorzio Per La Ricerca Sulla Microelettronica Nel Mezzogiorno Schaltung zur Begrenzung des Maximalstroms, den ein Leistungstransistor an eine Last liefert
US5635868A (en) * 1993-08-18 1997-06-03 Consorzio Per La Ricerca Sulla Microelettronica Nel Mezzogiorno Power transistor current limiter

Also Published As

Publication number Publication date
EP0307325B1 (de) 1993-03-10
FR2619859A1 (fr) 1989-03-03
ES2038781T3 (es) 1993-08-01
KR890004068A (ko) 1989-04-19
FR2619859B1 (fr) 1990-01-12
JP2621946B2 (ja) 1997-06-18
US4912373A (en) 1990-03-27
JPS6473168A (en) 1989-03-17
DE3879051D1 (de) 1993-04-15
DE3879051T2 (de) 1993-09-16

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