CN113741613A - Zero-temperature-adjustable ACOT charging current circuit - Google Patents

Zero-temperature-adjustable ACOT charging current circuit Download PDF

Info

Publication number
CN113741613A
CN113741613A CN202111127933.3A CN202111127933A CN113741613A CN 113741613 A CN113741613 A CN 113741613A CN 202111127933 A CN202111127933 A CN 202111127933A CN 113741613 A CN113741613 A CN 113741613A
Authority
CN
China
Prior art keywords
tube
charging current
npn
electrode
acot
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
CN202111127933.3A
Other languages
Chinese (zh)
Other versions
CN113741613B (en
Inventor
周泽坤
龚州
任航
王卓
张波
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.)
University of Electronic Science and Technology of China
Original Assignee
University of Electronic Science and Technology of China
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 University of Electronic Science and Technology of China filed Critical University of Electronic Science and Technology of China
Priority to CN202111127933.3A priority Critical patent/CN113741613B/en
Publication of CN113741613A publication Critical patent/CN113741613A/en
Application granted granted Critical
Publication of CN113741613B publication Critical patent/CN113741613B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
    • G05F1/10—Regulating voltage or current
    • G05F1/46—Regulating voltage or current wherein the variable actually regulated by the final control device is dc
    • G05F1/56—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices
    • G05F1/565—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices sensing a condition of the system or its load in addition to means responsive to deviations in the output of the system, e.g. current, voltage, power factor
    • G05F1/567—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices sensing a condition of the system or its load in addition to means responsive to deviations in the output of the system, e.g. current, voltage, power factor for temperature compensation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

The invention belongs to the technical field of switching power supplies, and particularly relates to a zero-temperature-adjustable ACOT charging current circuit. The invention utilizes the negative temperature characteristic of the voltage of the base electrode-emitter electrode (BE junction) of the triode, respectively utilizes the modes of series connection and parallel connection of the resistor and the BE junction of the triode to generate positive temperature coefficient current and negative temperature coefficient current, and can realize zero temperature coefficient charging current by reasonably setting the current coefficient. The invention has the beneficial effect of overcoming the defects that the traditional ACOT charging current changes along with the temperature and is not adjustable after being formed into a chip. The ACOT charging current circuit not only generates a current irrelevant to temperature, but also can adjust the size of the internal charging current by changing the size of the external resistor.

Description

Zero-temperature-adjustable ACOT charging current circuit
Technical Field
The invention belongs to the technical field of switching power supplies, and particularly relates to a zero-temperature-adjustable ACOT charging current circuit.
Background
With the continuous development of the electronic industry, the demand of electronic products for high-performance power management chips is also increasing. A Constant On-time (COT) controlled Buck converter is favored by virtue of its simple structure, high efficiency and fast response speed. An Adaptive Constant On-time (ACOT) technology developed On the basis of a COT circuit can eliminate the problem of Electromagnetic Interference (EMI) caused by frequency jitter of a switching power supply by means of the characteristic of pseudo Constant frequency, so that the application of the ACOT switching power supply is wider. The core of the ACOT circuit for realizing the constant frequency lies in generating a charging current circuit which is positively correlated with the power supply voltage, but the charging current of the traditional ACOT charging current circuit can change along with the charging time, and the temperature coefficient of the charging current is not considered. These disadvantages may cause the operating frequency of the system to change when the switching power supply chip operates under different environments, thereby affecting the stability of the chip system.
In addition, for frequency conversion application scenes (such as LED driving), the traditional ACOT charging current is only related to the internal circuit of the chip, and the switching frequency of the system is fixed after the chip is packaged, so that the frequency conversion control cannot be realized, and the application of the ACOT switching power supply is greatly limited.
Disclosure of Invention
The invention aims to generate a charging current which does not change along with the charging time and the external temperature, greatly improves the pseudo-constant frequency characteristic of ACOT, and ensures the stability of the system in working under different environments. In addition, according to the working environment setting of the chip, the magnitude of the charging current can be changed linearly by adjusting the external resistor, so that the working frequency of the chip is adjusted at high precision, and the inductor-capacitor type selection range of the ACOT switching power supply circuit is greatly widened.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the invention aims to solve the problems of the conventional ACOT charging current, and provides a zero-temperature adjustable ACOT charging current circuit, which not only realizes the zero-temperature characteristic of the charging current, but also can set the working frequency of a switching power supply by adjusting the external resistance of a chip and changing the magnitude of the ACOT charging current.
The technical scheme of the invention is as follows: the zero temperature adjustable ACOT charging current circuit includes: a positive temperature coefficient (PTAT) charging current circuit, a negative temperature Coefficient (CTAT) charging current circuit, and a current superposition circuit. The PTAT charging current circuit is mainly formed by connecting a BJT, a high-voltage enabling tube LDMOS and an external resistor R in series; the PTAT current is generated on the external resistor by utilizing the negative temperature characteristic of the BJT, and the magnitude of the charging current can be changed by modifying the magnitude of the external resistor, so that the working frequency is changed. The CTAT charging current circuit mainly comprises a BJT and a resistor R1 which are connected in parallel, and the negative temperature characteristic voltage of the BJT is transferred to a resistor R1, so that negative temperature coefficient current is generated. The current superposition circuit mainly comprises a plurality of low-voltage MOS current mirrors and BJT current mirrors, and finally realizes superposition of PTAT current and CTAT current to obtain zero-temperature current.
The positive temperature coefficient charging current circuit comprises a first NLDMOS tube, a first NPN tube and an external resistor; the negative temperature coefficient charging current circuit comprises an internal bias current IBIASThe second PMOS tube, the third PMOS tube, the fourth PMOS tube, the third NPN tube, the fourth NPN tube and the first resistor R1; the current superposition circuit comprises a first PMOS (P-channel metal oxide semiconductor) tube, a first NMOS (N-channel metal oxide semiconductor) tube, a second NMOS tube and a second NPN (negative-positive-negative) tube;
one end of the internal resistor is connected with an external input signal VIN, and the other end of the internal resistor is connected with a drain electrode of the first NLDMOS tube; the grid electrode of the first NLDMOS tube is connected with an internal ACOT enabling signal, and the source electrode of the first NLDMOS tube is connected with the collector electrode and the base electrode of the first NPN tube and the base electrode of the second NPN tube;
the grid electrode of the third PMOS tube and the grid electrode of the fourth PMOS tube are connected with the drain electrode of the fourth PMOS tube and the input end of the internal bias current; the drain electrode of the third PMOS tube is connected with the collector electrode of the third NPN tube and the base electrode of the fourth NPN tube;
the base electrode of the third NPN tube is connected with the emitter electrode of the fourth NPN tube and one end of the first resistor R1; a collector of the fourth NPN tube is connected with a drain electrode and a grid electrode of the second PMOS tube and a grid electrode of the first PMOS tube;
the grid electrode of the first NMOS tube is connected with the grid electrode and the drain electrode of the second NMOS tube, and the drain electrode of the first NMOS tube is connected with the collector electrode of the second NPN tube to form current superposition;
the source electrodes of the first PMOS tube, the second PMOS tube, the third PMOS tube and the fourth PMOS tube are connected with a power supply VDD;
the emitting electrodes of the first NPN tube, the second NPN tube and the third NPN tube, the source electrodes of the first NMOS tube and the second NMOS tube, the other end of the first resistor and the output end of the internal bias current are all grounded.
The invention has the beneficial effect of overcoming the defects that the traditional ACOT charging current changes along with the temperature and is not adjustable after being formed into a chip. The ACOT charging current circuit not only generates a current irrelevant to temperature, but also can adjust the size of the internal charging current by changing the size of the external resistor.
Drawings
Fig. 1 shows an ACOT charging current circuit according to the present invention.
Fig. 2 is a schematic diagram of the zero-temperature charging current generation of the ACOT charging current circuit according to the present invention.
Fig. 3 is a graph showing the variation of the charging current and the operating frequency of the ACOT charging current circuit according to the present invention.
Detailed Description
The technical scheme of the invention is described in detail below with reference to the accompanying drawings:
the ACOT charging current circuit proposed by the present invention is shown in fig. 1. When the internal enable signal EN is low, the PTAT current path is disconnected, the ACOT module does not work, the drain end of the first NLDMOS tube resists high voltage, and an internal circuit is protected; when EN is turned over to be high, the first NLDMOS tube works in a linear region, the on-resistance of the first NLDMOS tube is small and can be ignored, and the first NLDMOS tube is based on the triode VBETheoretical expression of voltage variation with temperature:
Figure BDA0003279485290000031
wherein Vg0Zero time silicon bandgap voltage, TrFor reference temperature, VTrFor thermal voltage at a reference temperature, η is a constant related to the process, x represents a temperature coefficient of current flowing through a collector of the triode, and x is expressed as:
Figure BDA0003279485290000032
ignore VBEThe voltage is higher than the temperature term, and then the PTAT current flowing through the first NPN tube is expressed as:
Figure BDA0003279485290000033
similarly, the CTAT current is obtained by dividing the base-emitter voltage of the third NPN transistor by the first resistor R1Obtained, therefore the CTAT current expression is:
Figure BDA0003279485290000034
in summary, the I output finally passes through the current superposition circuitACOTThe current expression is:
Figure BDA0003279485290000035
when R is1＝RonWhen, IACOTThe current has a zero temperature coefficient characteristic.
Fig. 2 is a schematic diagram of the zero-temperature charging current generation of the ACOT charging current circuit. The ACOT charging current with zero temperature coefficient is realized by superposing the charging current with positive temperature characteristic and the charging current with negative temperature characteristic.
FIG. 3 is a graph of the variation of the charging current and operating frequency of the ACOT charging current circuit with the external resistance. According to the formula (5), the external resistance is increased, the total ACOT charging current is reduced, the inverse proportional relation is satisfied, and the frequency conversion function can be realized. Due to RonAnd R1In the same order of magnitude, and VIN>>VgoTherefore, the dominant terms of the ACOT charging current are the input voltage VIN and the external resistor RonThe remaining terms are negligible, i.e., the ACOT charging current approximately satisfies the expression:
Figure BDA0003279485290000041
then the power supply t is switched on and offonThe time satisfies the expression:
Figure BDA0003279485290000042
therefore, the operating frequency of the switching power supply meets the expression:
Figure BDA0003279485290000043
in summary, the ACOT charging current circuit provided by the invention generates a charging current meeting zero temperature and adjustable outside simultaneously on the premise of not increasing circuit complexity, thereby greatly widening the application range of the ACOT circuit.

Claims (1)

1. A zero-temperature-adjustable ACOT charging current circuit is characterized by comprising a positive temperature coefficient charging current circuit, a negative temperature coefficient charging current circuit and a current superposition circuit; the positive temperature coefficient charging current circuit comprises a first NLDMOS tube, a first NPN tube and an external resistor; the negative temperature coefficient charging current circuit comprises an internal bias current IBIASThe second PMOS tube, the third PMOS tube, the fourth PMOS tube, the third NPN tube, the fourth NPN tube and the first resistor R1; the current superposition circuit comprises a first PMOS (P-channel metal oxide semiconductor) tube, a first NMOS (N-channel metal oxide semiconductor) tube, a second NMOS tube and a second NPN (negative-positive-negative) tube;
one end of the internal resistor is connected with an external input signal VIN, and the other end of the internal resistor is connected with a drain electrode of the first NLDMOS tube; the grid electrode of the first NLDMOS tube is connected with an internal ACOT enabling signal, and the source electrode of the first NLDMOS tube is connected with the collector electrode and the base electrode of the first NPN tube and the base electrode of the second NPN tube;
the grid electrode of the third PMOS tube and the grid electrode of the fourth PMOS tube are connected with the drain electrode of the fourth PMOS tube and the input end of the internal bias current; the drain electrode of the third PMOS tube is connected with the collector electrode of the third NPN tube and the base electrode of the fourth NPN tube;
the base electrode of the third NPN tube is connected with the emitter electrode of the fourth NPN tube and one end of the first resistor R1; a collector of the fourth NPN tube is connected with a drain electrode and a grid electrode of the second PMOS tube and a grid electrode of the first PMOS tube;
the grid electrode of the first NMOS tube is connected with the grid electrode and the drain electrode of the second NMOS tube, and the drain electrode of the first NMOS tube is connected with the collector electrode of the second NPN tube to form current superposition;
the source electrodes of the first PMOS tube, the second PMOS tube, the third PMOS tube and the fourth PMOS tube are connected with a power supply VDD;
the emitting electrodes of the first NPN tube, the second NPN tube and the third NPN tube, the source electrodes of the first NMOS tube and the second NMOS tube, the other end of the first resistor and the output end of the internal bias current are all grounded.
CN202111127933.3A 2021-09-26 2021-09-26 Zero-temperature-adjustable ACOT charging current circuit Active CN113741613B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111127933.3A CN113741613B (en) 2021-09-26 2021-09-26 Zero-temperature-adjustable ACOT charging current circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111127933.3A CN113741613B (en) 2021-09-26 2021-09-26 Zero-temperature-adjustable ACOT charging current circuit

Publications (2)

Publication Number Publication Date
CN113741613A true CN113741613A (en) 2021-12-03
CN113741613B CN113741613B (en) 2022-05-17

Family

ID=78741010

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111127933.3A Active CN113741613B (en) 2021-09-26 2021-09-26 Zero-temperature-adjustable ACOT charging current circuit

Country Status (1)

Country Link
CN (1) CN113741613B (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2120124A1 (en) * 2008-05-13 2009-11-18 STMicroelectronics S.r.l. Circuit for generating a temperature-compensated voltage reference, in particular for applications with supply voltages lower than 1V
CN101901018A (en) * 2009-05-26 2010-12-01 上海华虹Nec电子有限公司 Voltage reference circuit
US20140070873A1 (en) * 2012-09-07 2014-03-13 Nxp B.V. Low-power resistor-less voltage reference circuit
CN104467095A (en) * 2014-12-09 2015-03-25 芯荣半导体有限公司 Constant-current and constant-voltage charger chip based on ACOT framework
CN105915054A (en) * 2016-06-06 2016-08-31 电子科技大学 BUCK converter based on ACOT control mode
CN207218640U (en) * 2017-08-08 2018-04-10 深圳市锦锐科技有限公司 High-precision internal oscillator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2120124A1 (en) * 2008-05-13 2009-11-18 STMicroelectronics S.r.l. Circuit for generating a temperature-compensated voltage reference, in particular for applications with supply voltages lower than 1V
CN101901018A (en) * 2009-05-26 2010-12-01 上海华虹Nec电子有限公司 Voltage reference circuit
US20140070873A1 (en) * 2012-09-07 2014-03-13 Nxp B.V. Low-power resistor-less voltage reference circuit
CN104467095A (en) * 2014-12-09 2015-03-25 芯荣半导体有限公司 Constant-current and constant-voltage charger chip based on ACOT framework
CN105915054A (en) * 2016-06-06 2016-08-31 电子科技大学 BUCK converter based on ACOT control mode
CN207218640U (en) * 2017-08-08 2018-04-10 深圳市锦锐科技有限公司 High-precision internal oscillator

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
SHIKHAR TEWARI: "Intuitive design of PTAT and CTAT circuits for MOSFET based temperature sensor using Inversion Coefficient based approach", 《IEEE》 *
周泽坤等: "一种基于ACOT的高效降压型DC/DC变换器", 《微电子学》 *

Also Published As

Publication number Publication date
CN113741613B (en) 2022-05-17

Similar Documents

Publication Publication Date Title
CN101840240B (en) Adjustable multi-value output reference voltage source
CN109062310A (en) A kind of low-power consumption band-gap reference circuit with source compensated by using high-order curvature
WO2023005806A1 (en) Ldo circuit having power supply rejection function, chip and communication terminal
CN114296503B (en) Ultra-low power consumption programmable low dropout linear voltage regulator circuit
CN110673685A (en) Ultra-low power consumption voltage reference circuit
CN111427411A (en) Integrated output circuit capable of being used for adjusting temperature coefficient
CN113934250B (en) Low temperature coefficient and high power supply rejection ratio high-low voltage conversion circuit
Huang et al. A 10 nA ultra-low quiescent current and 60 ns fast transient response low-dropout regulator for Internet-of-Things
CN113741613B (en) Zero-temperature-adjustable ACOT charging current circuit
CN210666511U (en) Ultra-low power consumption voltage reference circuit
CN109388171B (en) Band gap reference voltage source and electronic equipment
CN203643886U (en) Band-gap reference source circuit and band-gap reference source
CN116185115A (en) LDO composite zero tracking compensation circuit
CN214253044U (en) Current source circuit and electronic equipment
CN115333367A (en) Voltage conversion circuit
CN101763137A (en) Current generating circuit
Yang et al. Design of high-power white LED drive chip with fully integrated PWM dimming function
CN110445377B (en) Conduction time generating circuit with zero static power consumption
CN109274268B (en) High-voltage to low-voltage circuit applied to chip interior
CN218332402U (en) Band gap reference source circuit and electronic equipment
CN111399580A (en) Linear voltage stabilizing circuit
CN111176361A (en) Sub-threshold band-gap reference voltage source based on substrate bias regulation
CN117059020B (en) LED display screen driving circuit with low turning voltage and LED display screen
CN114815949B (en) Wide-range fast response voltage stabilizer
CN112306143B (en) Simple negative voltage reference circuit

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant