EP1186983A2 - Geschalteter Bandabstandsregler - Google Patents

Geschalteter Bandabstandsregler Download PDF

Info

Publication number
EP1186983A2
EP1186983A2 EP01120556A EP01120556A EP1186983A2 EP 1186983 A2 EP1186983 A2 EP 1186983A2 EP 01120556 A EP01120556 A EP 01120556A EP 01120556 A EP01120556 A EP 01120556A EP 1186983 A2 EP1186983 A2 EP 1186983A2
Authority
EP
European Patent Office
Prior art keywords
voltage
circuit
generator
regulator
node
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.)
Withdrawn
Application number
EP01120556A
Other languages
English (en)
French (fr)
Other versions
EP1186983A3 (de
Inventor
Franco Cocetta
Giorgio Rossi
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 SRL
Original Assignee
STMicroelectronics SRL
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
Priority claimed from EP00830594A external-priority patent/EP1184954A1/de
Application filed by STMicroelectronics SRL filed Critical STMicroelectronics SRL
Priority to EP01120556A priority Critical patent/EP1186983A3/de
Publication of EP1186983A2 publication Critical patent/EP1186983A2/de
Publication of EP1186983A3 publication Critical patent/EP1186983A3/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F3/00—Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties
    • G05F3/02—Regulating voltage or current
    • G05F3/08—Regulating voltage or current wherein the variable is dc
    • G05F3/10—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics
    • G05F3/16—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices
    • G05F3/20—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices using diode- transistor combinations
    • G05F3/30—Regulators using the difference between the base-emitter voltages of two bipolar transistors operating at different current densities

Definitions

  • This invention relates to a switching type bandgap controller.
  • the invention relates to a self-powered electronic circuit for regulating a stable reference voltage, which circuit comprises a band-gap generator to produce said stable reference voltage, comprises a system circuit block supplied by a controlled voltage obtained from said reference voltage through a comparator and an error amplifier to output a regulated voltage, and comprises a regulating loop inserted between said output and the output of the band-gap generator and including a normalizer block.
  • the invention also relates to a regulating method implemented by said electronic circuit.
  • the invention relates to a voltage regulator for automotive applications, and the following description will cover this application field for convenience of illustration.
  • band-gap regulating system For instance in the technology of electronic microcircuits, a so-called band-gap regulating system is often used which is intended to generate a stable voltage reference from a usually pre-stabilized dedicated supply line.
  • the alternator output voltage 26 is compared with the band-gap reference voltage inside the comparator 44.
  • the reference voltage source 28 is an independent block.
  • the German patent No. DE 196 20 181 C relates to a circuit block for producing a reference output voltage Vout.
  • the reference output voltage is obtained from these two values.
  • FIG. 1 of the accompanying drawings a block diagram (A) is shown that provides an example of how a reference voltage signal Vr is generated.
  • the reference voltage signal Vr also known as the set-point signal, is generated by a Band-Gap block 11 connected to a supply line 5.
  • the signal SENSE at the output node OUT represents the variable to be controlled, that is the output signal of a system block 2 which may be for example a drive circuit portion of an alternator.
  • This signal SENSE following to a normalizing phase inside a block 3 placed in a feedback loop, is compared with the reference voltage signal Vr, through the block 4, in order to generate a control voltage of the system block 2.
  • the signals involved in the loop regulator circuit 1 are translated into voltage signals using small amounts of electric power.
  • the supply line, designated at 5 in the scheme of Figure 1 is not always stabilized. In fact, in some applications as the ones of the voltage regulators for automotive alternators, the supply voltage on the line 5 may show negative pulses of considerable depth and duration, as shows the diagram of Figure 2.
  • the ordinate of this diagram is the output voltage VGO (Voltage Generator Output) of an automotive alternator, which also represents the supply to the regulator circuit 1 on the line 5.
  • the controlled signal SENSE is represented by the battery voltage of the vehicle. It can be understood that, since the average voltage of the controlled signal is of 14.5V and the fast surges of about 15V, the minimum voltage on the supply line 5 may drop to zero volt and below.
  • a regulator circuit of hybrid structure that is of the type comprising a monolithically integrated portion and a discrete component portion, could be used.
  • This alternative solution allows to solve the surge problem, since the hybrid technology provides for sufficient capacitance values to counterbalance the voltage drops.
  • the same structure available in hybrid form is obviously not proposable in a totally integrated form, since the capacitances of the required value can paractically not be integrated.
  • the underlying technical problem of this invention is to provide an integrated electronic circuit for regulating a stable reference voltage, which circuit has such structural, functional and consumption features such that it can be realised by a reduced number of components.
  • the electronic circuit of the invention should be supplied by one of the voltage signals produced inside the circuit itself, thereby lowering the overall power consumption and improving the stable characteristics of the generated reference voltage signal Vr.
  • a further aim is that of realising an electronic circuit able to follow dynamically the system block, thus operating in a switching mode.
  • the resolution idea on which this invention stands is that of using, as the supply voltage, the controlled signal SENSE produced by the system block itself, and applying such supply voltage to a band-gap regulator which additionally includes comparing and error amplifying means.
  • the band-gap circuit portion intended to generate a stable voltage reference from the supply voltage, is to carry out the following functions:
  • the invention further relates to a regulating method as defined in Claim 10.
  • an integrated electronic circuit according to the invention for regulating a stable reference voltage Vr, is generally shown at 10 in schematic form.
  • the circuit 10 may be defined as a switching type band-gap controller.
  • the circuit 10 comprises a band-gap generator 11 intended to provide a control voltage Vc to a system block 12.
  • a voltage signal SENSE is picked up at the output OUT of the system block 12 and it is directly transferred to the band-gap generator 11 through a normalizing block 13.
  • the voltage signal SENSE is therefore used to power the band-gap, error amplification and comparison circuit portions which are inserted in the regulating loop of the circuit 10.
  • the circuit 10 is useful in automotive applications, and accordingly, would be installed on an automobile vehicle which is also equipped with an alternator associated to propulsion means.
  • the alternator output voltage VGO although affected by noise, is used in this invention to power less critical areas of the vehicle own electronic circuitry.
  • the band-gap generator 11 combines the functions of:
  • the circuit of Figure 4 includes an operational amplifier OP1 effective to regulate the voltage of a node A so that the potentials of the nodes B and B' can be made to coincide. Since the nodes B and B' are connected to the node A through resistors R1 with the same value, and are coupled to ground through respective transistors Q1 and Q2 diode-connected in the generator, the same current Io will be flowing through the respective circuit legs containing such transistors.
  • Vr Vbe(Q1) + ⁇ Vbe*R1/R0
  • Vs The value of the controlled voltage,- designated Vs, presented on the SENSE line can be obtained from equation (3) below on account of the regulating loop.
  • circuit of this invention shown in Figure 5, allows equation 3 to be applied directly to the signal Vs from the band-gap reference generator of Figure 4.
  • the band-gap generator 11 of this invention is powered from the line SENSE directly picked up from the output OUT of the system block 12 ( Figure 3).
  • the block 13 may be considered incorporated inside the new block 11, as will be clarified in the following lines.
  • the generator 11 comprises a first circuit leg connecting the SENSE line to ground and including a complementary pair of bipolar transistors, namely a pnp transistor Q7 connected to an npn transistor Q4 at a node C.
  • a second circuit leg connects the SENSE line to ground and includes a complementary pair of bipolar transistors, namely a pnp transistor Q6 connected to an npn transistor Q3.
  • the bases of the transistors Q7, Q6 are connected together. Also, the transistor Q6 is a diode configuration so as to form a current mirror in combination with the transistor Q7. Thus, a current Io will flow through each of said legs.
  • the first and second circuit legs form an external current mirror, as against the internal current mirror of the band-gap generator of Figure 4, in place of the error amplifier provided by the prior art.
  • a third circuit leg connects the SENSE line to ground, but branches off into additional legs as described herein below.
  • a first connection of the third leg includes a resistive divider 15 connecting a node S, that is the SENSE line, to ground through a resistor pair connected to a node R from which the signal Vr is picked up.
  • a second connection of the third leg includes an npn bipolar transistor Q5 which is connected in series with a resistor R2.
  • the base of the transistor Q5 is connected to said node R of the divider 15.
  • the transistor Q5 and the divider 15 implement the block 13 in Figure 3.
  • the transistor Q1 is a diode configuration and has its base interconnected with the base of the transistor Q4 of the first circuit leg. This interconnection represents a circuit node B.
  • the diode-configured transistor Q2 has its base coinciding with a circuit node B'.
  • the base of the transistor Q3 in the second circuit leg is connected to the inteconnection node between the resistors R1 and R0.
  • the node A is accessible to receive a current ramp Ipwr.
  • the node C of the first circuit leg is connected to ground through a Zener diode Dz1 and connected to the gate terminal of an N-channel field-effect transistor MDR to drive a circuit portion 16 which is associated with a vehicle alternator being a part of the system block 12.
  • a power transistor e.g. an N-channel MOS transistor MPWR, has one conduction terminal coupled to an alternator coil through a resistor RF, and has the other conduction terminal connected to ground.
  • a loop-back diode Dr Placed in parallel to the series of the coil and the resistor RF is a loop-back diode Dr connecting a node F to a line supplying a signal VGO.
  • a resistive divider is placed between this supply line VGO and the ground, which divider is made of at least two resistors Rd1, Rd2 and is coupled to the supply line VGO and to the ground through respective diodes. More particularly, a diode Dd is inserted between the supply line VGO and the divider, while a Zener diode Dz2 is inserted between ground and the divider.
  • One conduction terminal of the drive transistor MDR of the circuit portion 16 is connected to the interconnection node D between the divider resistors Rd1, Rd2, while the other conduction terminal of the transistor MDR is connected to ground.
  • the generator 11 Compared with the circuit layout of a conventional band-gap generator, such as that shown in Figure 4, the generator 11 has the transistor pair Q3, Q4 in place of the error amplifier OP1 of Figure 4. In essence, it is as if the band-gap generator 11, as a whole, were also having an error amplifier function.
  • the transistor Q5 selected with twice the area than the transistor Q1 to set the desired regulation voltage at the SENSE node, takes the place of the voltage "normalizer" block according to the prior art.
  • the current mirror or similar, formed from the transistors Q6 and Q7 to create the comparison function (node C), instead of the prior art comparator shown in Figure 1A;
  • Vs/K Vbe(Q1)+R1/R0* ⁇ Vbe+2*R2* ⁇ Vbe/R0+Vbe(Q5)
  • equation (4) essentially represents the sum of two "band-gap" equations and is, therefore, fully controllable.
  • the ramp current Ipwm should be generated by a generator of a constant voltage Vpwm which may be very small ( ⁇ 0.5V) as indicated by the following equations.
  • VpwmM the highest value attained by the ramp current
  • ⁇ Vs K*R2*IpwmM
  • Equation 6 is wholly independent of the value of slope vs. temperature assigned to Vs. This is another advantage over the prior art structure of Figure 1.
  • Regulators for use with alternators usually require that dVs/dT be other than zero and negative. In the conventional regulator of Figure 1, this is obtained by assigning an adequate slope vs. temperature to the reference voltage signal Vr. In the PWM regulator, this compels the average value of the voltage ramp to be also made to depend on temperature and according to the same rule, in order not to miss the modulation gain.
  • the additional current required for the circuit of Figure 5 to operate is four times larger than the current Io set by the area ratio of the transistors Q1 and Q2, and the resistance value of the resistor R0.
  • the current 4*Io becomes like that shown in the experimental graph of Figure 6.
  • the generator circuit structure could be obtained using MOS instead of bipolar transistors.
  • the layout of the generator 11 can be easily adapted by inserting an npn bipolar transistor Q9 in between the SENSE line and the collector of Q5, node S.
  • the base of the transistor Q9 would be connected in a connection node C between the transistors Q6 and Q3 of the second circuit leg and coupled to ground through a capacitor for the dynamic stabilisation.
  • the node S would become the regulated output of the generator circuit in the linear mode, as schematically shown in Figure 7.
  • the general inventive concept of the present invention is to supply all the block 11, 6, 4 and 3 of the prior art by the output signal on the output node S.
  • the reference voltage produced by the Band-Gap block 11 may be obtained through another kind of voltage regulator, for instance a voltage reference obtained by a zener diode.
  • the electronic circuit according to the present invention is capable of directly controlling the system block 12.
  • the control phase is advantageously performed in a switching mode, the linear mode being also available as an option.
  • the circuit block 11 doesn't require an external supply voltage since it is supplied by the signal SENSE that is the output of the system block. This block 11 provides the output voltage Vc for controlling the system block 12.
  • the electronic circuit of the invention allows a switching control of the system block 12 since it works in a switching mode even inside.
  • the current and voltages inside the inventive circuit are variable in time and not only with temperature.

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Nonlinear Science (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Automation & Control Theory (AREA)
  • Control Of Electrical Variables (AREA)
EP01120556A 2000-08-31 2001-08-29 Geschalteter Bandabstandsregler Withdrawn EP1186983A3 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP01120556A EP1186983A3 (de) 2000-08-31 2001-08-29 Geschalteter Bandabstandsregler

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP00830594 2000-08-31
EP00830594A EP1184954A1 (de) 2000-08-31 2000-08-31 Selbsgespeister und Integrierter Spannungsregler und dazugehöriges Regelungsverfahren
EP01120556A EP1186983A3 (de) 2000-08-31 2001-08-29 Geschalteter Bandabstandsregler

Publications (2)

Publication Number Publication Date
EP1186983A2 true EP1186983A2 (de) 2002-03-13
EP1186983A3 EP1186983A3 (de) 2003-11-12

Family

ID=26074164

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01120556A Withdrawn EP1186983A3 (de) 2000-08-31 2001-08-29 Geschalteter Bandabstandsregler

Country Status (1)

Country Link
EP (1) EP1186983A3 (de)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4110677A (en) * 1977-02-25 1978-08-29 Beckman Instruments, Inc. Operational amplifier with positive and negative feedback paths for supplying constant current to a bandgap voltage reference circuit
EP0656574A1 (de) * 1993-12-02 1995-06-07 Consorzio per la Ricerca sulla Microelettronica nel Mezzogiorno - CoRiMMe Spannungsreferenz mit linearem negativem Temperaturkoeffizienten
EP0713166A1 (de) * 1994-11-15 1996-05-22 STMicroelectronics Limited Spannungsreferenzschaltung
US5770940A (en) * 1995-08-09 1998-06-23 Switch Power, Inc. Switching regulator
EP0971280A1 (de) * 1998-07-07 2000-01-12 Motorola Semiconducteurs S.A. Spannungsregler und Verfahren zur Spannungsregelung

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4110677A (en) * 1977-02-25 1978-08-29 Beckman Instruments, Inc. Operational amplifier with positive and negative feedback paths for supplying constant current to a bandgap voltage reference circuit
EP0656574A1 (de) * 1993-12-02 1995-06-07 Consorzio per la Ricerca sulla Microelettronica nel Mezzogiorno - CoRiMMe Spannungsreferenz mit linearem negativem Temperaturkoeffizienten
EP0713166A1 (de) * 1994-11-15 1996-05-22 STMicroelectronics Limited Spannungsreferenzschaltung
US5770940A (en) * 1995-08-09 1998-06-23 Switch Power, Inc. Switching regulator
EP0971280A1 (de) * 1998-07-07 2000-01-12 Motorola Semiconducteurs S.A. Spannungsregler und Verfahren zur Spannungsregelung

Also Published As

Publication number Publication date
EP1186983A3 (de) 2003-11-12

Similar Documents

Publication Publication Date Title
EP0500381B1 (de) Adaptiver Spannungsregler
US5861771A (en) Regulator circuit and semiconductor integrated circuit device having the same
US5625278A (en) Ultra-low drop-out monolithic voltage regulator
US5666044A (en) Start up circuit and current-foldback protection for voltage regulators
US6498466B1 (en) Cancellation of slope compensation effect on current limit
US4823070A (en) Switching voltage regulator circuit
US5939867A (en) Low consumption linear voltage regulator with high supply line rejection
USRE42335E1 (en) Single transistor-control low-dropout regulator
EP0846996A1 (de) Leistungstransistorsteuerschaltung für Spannungsregler
US6593725B1 (en) Feed-forward control for DC-DC converters
US7176668B2 (en) Switching regulator with advanced slope compensation
US6507178B2 (en) Switching type bandgap controller
US5929616A (en) Device for voltage regulation with a low internal dissipation of energy
KR20040104924A (ko) 스위칭 레귤레이터
JP2005011067A (ja) 定電圧発生器
KR20010022479A (ko) 벅 부스트 스위칭 조정기
US5917312A (en) System and method for voltage positioning a regulator and regulator employing the same
EP1840693A1 (de) Verfahren und Vorrichtung für eine spannungsausgelöste Stromsenkschaltung
EP2804067B1 (de) Leistungsarmer LDO-Spannungsregler mit geringer Ausgangsrauschdichte
JP4234321B2 (ja) 調整器
US5122945A (en) Voltage controlled preload
US6005303A (en) Linear voltage regulator compatible with bipolar and MOSFET pass devices and associated methods
US6133766A (en) Control circuit for the current switch edges of a power transistor
US6486646B2 (en) Apparatus for generating constant reference voltage signal regardless of temperature change
EP1186983A2 (de) Geschalteter Bandabstandsregler

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

RIC1 Information provided on ipc code assigned before grant

Ipc: 7G 05F 1/565 B

Ipc: 7H 02M 3/156 A

17P Request for examination filed

Effective date: 20040507

AKX Designation fees paid

Designated state(s): DE FR GB IT

17Q First examination report despatched

Effective date: 20080317

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20080729