CN202351730U - Band-gap reference circuit, power protection circuit and power supply - Google Patents

Abstract

The utility model is applied to the electronic filed, provides a band-gap reference circuit and a power protection circuit and a power supply. The band-gap reference circuit comprises a band-gap reference generation unit, a power supply potential band-gap reference generation unit and a ground potential band-gap reference generation unit, the input end of the power supply potential band-gap reference generation unit is connected with power supply voltage, and the output end of the power supply potential band-gap reference generation unit is connected with the input end of the band-gap reference generation unit. The input end of the ground potential band-gap reference generation unit is connected with the output end of the band-gap reference generation unit, and the output end of the ground potential band-gap reference generation unit is connected with the ground. An embodiment generates band-gap current through two diode semiconductor accesses, relative power supply potential band-gap reference voltage and relative ground potential band-gap reference voltage are directly generated on a band-gap current branch circuit, and the two kinds of band-gap reference voltage generated by the circuit are good in consistency, low in consumption, small in area, fewer in circuit stage number and high in accuracy.

Description

A kind of band-gap reference circuit, power protecting circuit and power supply

Technical field

The utility model belongs to electronic applications, relates in particular to a kind of band-gap reference circuit, power protecting circuit and power supply.

Background technology

At present, along with the fast development of IC industry, band-gap reference circuit (claiming band-gap circuit again) with its good temperature stability, becomes the important component part of integrated circuit and electronic system.The band-gap circuit principle of work is: the diode forward forward voltage has negative temperature characteristic; And voltage difference is proportional to temperature (having positive temperature characterisitic) during the diode forward conducting of two different electric current densitys; Utilize the compensating action of these two kinds of voltages on temperature, obtain the lower voltage and current of temperature coefficient.

Usually; Band-gap reference circuit can only produce the bandgap voltage reference of relative power supply potential, perhaps can only produce earthy relatively bandgap voltage reference, but in practical application; For example in the lithium electric protection circuit; Need relative power supply potential and earthy relatively two reference voltages, to this, prior art adopts following two kinds of schemes usually:

One, use two band-gap reference circuits to produce relative power supply potential, earthy relatively bandgap voltage reference respectively; But this scheme power consumption is big, area is big; Two bandgap voltage reference consistance are poor, can't satisfy the demand of low-power consumption applied environment and small size encapsulation, and cost is high.

Two, utilize the band-gap reference generation unit to produce an earthy relatively bandgap voltage reference earlier, re-use impact damper and derive relative power supply potential and earthy relatively two voltages.

Fig. 1 shows the corresponding band-gap reference circuit structure of deriving of existing alternative plan, comprising: band-gap reference generation unit 11 is used to produce an earthy relatively bandgap voltage reference; And derived units 12; The input end of this derived units 12 is connected with the output terminal of band-gap reference generation unit 11, is used for deriving the bandgap voltage reference of relative power supply potential and earthy relatively bandgap voltage reference according to earthy relatively bandgap voltage reference.

Band-gap reference generation unit 11 comprises: P type metal-oxide-semiconductor P10, P type metal-oxide-semiconductor P11, P type metal-oxide-semiconductor P12, resistance R 13, resistance R 14, diode D10, diode D11, diode D12 and first operational amplifier A 1; The source class of P type metal-oxide-semiconductor P10, P type metal-oxide-semiconductor P11, P type metal-oxide-semiconductor P12 all is connected with supply voltage; The drain electrode of P type metal-oxide-semiconductor P11 is connected with the anode of diode D11 through resistance R 13; The plus earth of diode D11; The drain electrode of P type metal-oxide-semiconductor P11 also is connected with the positive input of first operational amplifier A 1; The drain electrode of P type metal-oxide-semiconductor P12 is connected with the reverse input end of first operational amplifier A 1 and the anode of diode D12 simultaneously; The plus earth of diode D12, the output terminal of first operational amplifier A 1 are connected with the grid of P type metal-oxide-semiconductor P10, P type metal-oxide-semiconductor P11, P type metal-oxide-semiconductor P12 respectively, and the drain electrode of P type metal-oxide-semiconductor P10 is connected with the anode of diode D10 through resistance R 14; The plus earth of diode D10, the drain electrode of P type metal-oxide-semiconductor P10 is the output terminal of band-gap reference generation unit 11;

Derived units 12 comprises: impact damper A2, resistance R 10, resistance R 11, resistance R 12, capacitor C 10, capacitor C 11 and N type metal-oxide-semiconductor N10; Resistance R 12 is parallelly connected with capacitor C 11; The one of which common port is connected with supply voltage; Another common port is connected with the drain electrode of N type metal-oxide-semiconductor N10, and parallelly connected with capacitor C 10 after resistance R 11 is connected with resistance R 10, resistance R 11 is connected with the source class of N type metal-oxide-semiconductor N10 with the common port of capacitor C 10; The common end grounding of resistance R 10 and capacitor C 10; Resistance R 10 is connected with the reverse input end of impact damper A2 with the common port of resistance R 11, and the positive input of impact damper A2 is the input end of derived units 12, and the output terminal of impact damper A2 is connected with the grid of N type metal-oxide-semiconductor N10.

Make the drain terminal voltage of P type metal-oxide-semiconductor P11 and P type metal-oxide-semiconductor P12 equate through first operational amplifier A 1; Produce the current branch that an electric current that is directly proportional with temperature flows through P type metal-oxide-semiconductor P11 and P type metal-oxide-semiconductor P12; P type metal-oxide-semiconductor P10 in the branch road of P10, and generates a temperature independent bandgap voltage reference V with diode D10, resistance R 14 with this current mirror _Bg, this bandgap voltage reference V _BgMake the voltage and the bandgap voltage reference V of its reverse input end through impact damper A2 _BgEquate, so that the electric current of deriving among the N type metal-oxide-semiconductor N10

Voltage

Voltage $V_{\mathrm{Ref}}$ ${12}_{}=(\mathrm{<figure-callout\; id="11"\; label="R"\; filenames="HDA0000112384390000011.png"\; state="\{\{state\}\}">R</figure-callout>}11+R10)\frac{V_{\mathrm{Bg}}}{R10},$ Through selecting resistance, the temperature-coefficient of electrical resistance of dividing out of same type, to obtain the bandgap voltage reference V of relative power supply potential _Ref11And earthy relatively bandgap voltage reference V _Ref12, wherein capacitor C 11 is respectively relative power supply potential bandgap voltage reference V with capacitor C 10 _Ref11Current potential bandgap voltage reference V relatively _Ref12Filtering.

Band-gap reference circuit can obtain two consistance voltage preferably though this is derived; And alleviate the problem that area is big, cost is high to a certain extent; But the band gap electric current makes circuit progression increase owing to derive; And then making voltage and earthy relatively voltage accuracy variation of the relative power supply potential of generation, power problems still exists simultaneously, is unfavorable for extensive popularization.

The utility model content

The purpose of the utility model embodiment is to provide a kind of band-gap reference circuit, and being intended to solve existing band-gap reference circuit provides that biobelt crack reference voltage power consumption is big, the problem of low precision.

The utility model embodiment is achieved in that a kind of band-gap reference circuit, and said band-gap reference circuit comprises:

Produce the band-gap reference generation unit of band gap electric current through two diode semiconductor paths;

According to said band gap electric current and supply voltage; On said band gap current branch, generate the power supply potential band-gap reference generation unit of relative power supply potential bandgap voltage reference; The input end of said power supply potential band-gap reference generation unit is connected with supply voltage, and the output terminal of said power supply potential band-gap reference generation unit is connected with the input end of said band-gap reference generation unit;

According to said band gap electric current and earth potential; On said band gap current branch, generate the earth potential band-gap reference generation unit of current potential bandgap voltage reference relatively; The input end of said earth potential band-gap reference generation unit is connected with the output terminal of said band-gap reference generation unit, and the output terminal of said earth potential band-gap reference generation unit is connected with ground.

Further, said band-gap reference generation unit comprises: first switching tube, second switch pipe, the 3rd operational amplifier, first diode semiconductor, second diode semiconductor, resistance R 21, resistance R 22 and resistance R 23;

The input end of said first switching tube is connected with the input end of said second switch pipe and is the input end of said band-gap reference generation unit simultaneously; Said first output end of switching tube is connected with the reverse input end of said the 3rd operational amplifier; The output terminal of said second switch pipe is connected with the positive input of said the 3rd operational amplifier; The output terminal of said the 3rd operational amplifier is connected with the control end of said first control end of switching tube, said second switch pipe respectively; Said first output end of switching tube also is connected with the input end of said first diode semiconductor; The output terminal of said first diode semiconductor is the output terminal of said band-gap reference generation unit; Said resistance R 21 is parallelly connected with said first diode semiconductor, and the output terminal of said second switch pipe also is connected with the input end of said second diode semiconductor through resistance R 23, and the output terminal of said second diode semiconductor is connected with the output terminal of said first diode semiconductor; One end of said resistance R 22 is connected with the output terminal of said second switch pipe, and the other end of said resistance R 22 is connected with the output terminal of said second diode semiconductor;

Power supply potential band-gap reference generation unit comprises: resistance R 20 and capacitor C 20; Said resistance R 20 is parallelly connected with said capacitor C 20; The one of which common port is the input end of said power supply potential band-gap reference generation unit, and another common port is the output terminal of said power supply potential band-gap reference generation unit;

Earth potential band-gap reference generation unit comprises: resistance R 24 and capacitor C 21; Said resistance R 24 is parallelly connected with said capacitor C 21; The one of which common port is the input end of said earth potential band-gap reference generation unit, and another common port is the output terminal of said earth potential band-gap reference generation unit.

Further; Said first switching tube and said second switch pipe are P type metal-oxide-semiconductor; The source class of said P type metal-oxide-semiconductor is the input end of said first switching tube, said second switch pipe; The drain electrode of said P type metal-oxide-semiconductor is the output terminal of said first switching tube, said second switch pipe, and the grid of said P type metal-oxide-semiconductor is the control end of said first switching tube, said second switch pipe.

Further, said first diode semiconductor and said second diode semiconductor are diode; Or

Said first diode semiconductor and said second diode semiconductor are transistor.

Further, said first diode semiconductor and said second diode semiconductor are vertical bipolar transistor; Or

Said first diode semiconductor and said second diode semiconductor are the MOS field effect transistor that works in accurate threshold zone.

Further, said band-gap reference generation unit comprises: the 3rd switching tube, the 4th switching tube, four-operational amplifier, the 3rd diode semiconductor, the 4th diode semiconductor, and resistance R 26;

The input end of said the 3rd switching tube is connected with the input end of said the 4th switching tube and is the input end of said band-gap reference generation unit simultaneously; Said the 3rd output end of switching tube is connected with the reverse input end of said four-operational amplifier; Said the 4th output end of switching tube is connected with the positive input of said four-operational amplifier; The output terminal of said four-operational amplifier is connected with said the 3rd control end of switching tube, said the 4th control end of switching tube respectively; Said the 3rd output end of switching tube also is connected with the input end of said the 3rd diode semiconductor; The output terminal of said the 3rd diode semiconductor is the output terminal of said band-gap reference generation unit; Said the 4th output end of switching tube also is connected with the input end of said the 4th diode semiconductor through resistance R 26, and the output terminal of said the 4th diode semiconductor is connected with the output terminal of said the 3rd diode semiconductor;

Power supply potential band-gap reference generation unit comprises: the 5th diode semiconductor, resistance R 25 and capacitor C 22; Connect with said resistance R 25 back and said capacitor C 22 of said the 5th diode semiconductor is parallelly connected; The anode of said the 5th diode semiconductor D5 is connected with an end of said capacitor C 22; Its common port is the input end of said power supply potential band-gap reference generation unit, and said resistance R 25 is the output terminal of said power supply potential band-gap reference generation unit with the common port of said capacitor C 22;

Earth potential band-gap reference generation unit comprises: the 6th diode semiconductor, resistance R 27 and capacitor C 23; Connect with said resistance R 27 back and said capacitor C 23 of said the 6th diode semiconductor is parallelly connected; The anode of said the 6th diode semiconductor is connected with an end of said capacitor C 23; Its common port is the input end of said earth potential band-gap reference generation unit, and said resistance R 27 is the output terminal of said earth potential band-gap reference generation unit with the common port of said capacitor C 23.

Further; Said the 3rd switching tube and said the 4th switching tube are P type metal-oxide-semiconductor; The source class of said P type metal-oxide-semiconductor is the input end of said the 3rd switching tube, said the 4th switching tube; The drain electrode of said P type metal-oxide-semiconductor is said the 3rd switching tube, said the 4th output end of switching tube, and the grid of said P type metal-oxide-semiconductor is said the 3rd switching tube, said the 4th control end of switching tube.

Further, said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are diode; Or

Said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are transistor; Or

Said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are vertical bipolar transistor; Or

Said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are the MOS field effect transistor that works in accurate threshold zone.

Another purpose of the utility model embodiment is to provide a kind of power protecting circuit that comprises above-mentioned band-gap reference circuit.

Another purpose of the utility model embodiment is to provide a kind of power supply that comprises above-mentioned power protecting circuit.

The utility model embodiment produces the band gap electric current through two diode semiconductor paths; And on this band gap current branch, directly generate relative power supply potential bandgap voltage reference and current potential bandgap voltage reference relatively; Two bandgap voltage reference high conformities that this circuit produces, low in energy consumption, area is little; And circuit progression is few, and precision is high.

Description of drawings

Fig. 1 is the existing band-gap reference circuit structural drawing of deriving;

The structural drawing of the band-gap reference circuit that Fig. 2 provides for the utility model one embodiment;

The first exemplary circuit structural drawing of the band-gap reference circuit that Fig. 3 provides for the utility model one embodiment;

The second exemplary circuit structural drawing of the band-gap reference circuit that Fig. 4 provides for the utility model one embodiment.

Embodiment

For the purpose, technical scheme and the advantage that make the utility model is clearer,, the utility model is further elaborated below in conjunction with accompanying drawing and embodiment.Should be appreciated that specific embodiment described herein only in order to explanation the utility model, and be not used in qualification the utility model.

The utility model embodiment produces the band gap electric current through two diode semiconductor paths; And on this band gap current branch, directly generate relative power supply potential bandgap voltage reference and current potential bandgap voltage reference relatively, and its biobelt crack reference voltage high conformity, low in energy consumption; Area is little, and precision is high.

Fig. 2 shows the structural drawing of the band-gap reference circuit that the utility model one embodiment provides, and for the ease of explanation, only shows the part relevant with the utility model embodiment.

The band-gap reference circuit that provides as the utility model one embodiment can be applicable to the power supply of any kind, and in the power protecting circuit of power supply, said band-gap reference circuit comprises:

Produce the band-gap reference generation unit 22 of band gap electric current through two diode semiconductor paths;

According to band gap electric current and supply voltage; On this band gap current branch, generate the power supply potential band-gap reference generation unit 21 of relative power supply potential bandgap voltage reference; The input end of this power supply potential band-gap reference generation unit 21 is connected with supply voltage, and the output terminal of power supply potential band-gap reference generation unit 21 is connected with the input end of band-gap reference generation unit 22;

According to band gap electric current and earth potential; On this band gap current branch, generate the earth potential band-gap reference generation unit 23 of relative power supply potential bandgap voltage reference; The input end of this earth potential band-gap reference generation unit 23 is connected with the output terminal of band-gap reference generation unit 22, and the output terminal of earth potential band-gap reference generation unit 23 is connected with ground.

Produce the band gap electric current at the utility model embodiment through two diode semiconductor paths; And on this band gap current branch, directly generate relative power supply potential bandgap voltage reference and current potential bandgap voltage reference relatively; Two bandgap voltage reference high conformities that this circuit produces, low in energy consumption, area is little; And circuit progression is few, and precision is high.

Be elaborated below in conjunction with the realization of specific embodiment to the utility model.

Fig. 3 shows the first exemplary circuit structure of the band-gap reference circuit that the utility model one embodiment provides, and for the ease of explanation, only shows the part relevant with the utility model embodiment.

As the utility model one embodiment, power supply potential band-gap reference generation unit 21 comprises:

Resistance R 20 and capacitor C 20, resistance R 20 is parallelly connected with capacitor C 20, and the one of which common port is the input end of power supply potential band-gap reference generation unit 21, and another common port is the output terminal of power supply potential band-gap reference generation unit 21;

Band-gap reference generation unit 22 comprises:

The first switching tube M1, second switch pipe M2, the 3rd operational amplifier A 3, the first diode semiconductor D1, the second diode semiconductor D2, resistance R 21, resistance R 22 and resistance R 23;

The input end of the first switching tube M1 is connected with the input end of second switch pipe M2 and is the input end of band-gap reference generation unit 22 simultaneously; The output terminal of the first switching tube M1 is connected with the reverse input end of the 3rd operational amplifier A 3; The output terminal of second switch pipe M2 is connected with the positive input of the 3rd operational amplifier A 3; The output terminal of the 3rd operational amplifier A 3 is connected with the control end of the first switching tube M1, the control end of second switch pipe M2 respectively; The output terminal of the first switching tube M1 also is connected with the input end of the first diode semiconductor D1; The output terminal of the first diode semiconductor D1 is the output terminal of band-gap reference generation unit 22; Resistance R 21 is parallelly connected with the first diode semiconductor D1, and the output terminal of second switch pipe M2 also is connected with the input end of the second diode semiconductor D2 through resistance R 23, and the output terminal of the second diode semiconductor D2 is connected with the output terminal of the first diode semiconductor D1; One end of resistance R 22 is connected with the output terminal of second switch pipe M2, and the other end of resistance R 22 is connected with the output terminal of the second diode semiconductor D2;

Earth potential band-gap reference generation unit 23 comprises: resistance R 24 and capacitor C 21, and resistance R 24 is parallelly connected with capacitor C 21, and the one of which common port is the input end of earth potential band-gap reference generation unit 23, and another common port is the output terminal of earth potential band-gap reference generation unit 23.

As the utility model one embodiment; The first switching tube M1 and second switch pipe M2 all can adopt P type metal-oxide-semiconductor to realize; The source class of P type metal-oxide-semiconductor is the input end of the first switching tube M1, second switch pipe M2; The drain electrode of P type metal-oxide-semiconductor is the output terminal of the first switching tube M1, second switch pipe M2, and the grid of P type metal-oxide-semiconductor is the control end of the first switching tube M1, second switch pipe M2.

As the utility model one embodiment; The first diode semiconductor D1 and the second diode semiconductor D2 all can adopt conventional diode to realize; The anode of this diode is the input end of the first diode semiconductor D1, the second diode semiconductor D2, and the negative electrode of diode is the output terminal of the first diode semiconductor D1, the second diode semiconductor D2.

As the utility model one embodiment, the first diode semiconductor D1 and the second diode semiconductor D2 also can adopt transistor to realize.

Preferably, the first diode semiconductor D1 and the second diode semiconductor D2 can adopt vertical bipolar transistor;

The first diode semiconductor D1 and the second diode semiconductor D2 also can adopt the MOS field effect transistor that works in accurate threshold zone.

In the utility model embodiment; PMOS pipe M1 and PMOS pipe M2 are measure-alike; Constitute current mirror, the electric current that promptly flows through PMOS pipe M1 and PMOS pipe M2 is equal, wherein; The electric current sum of the electric current of resistance R 21 and diode D1 equals the electric current among the PMOS pipe M1, and the series current of resistance R 23, diode D2 and the electric current sum of resistance R 22 equal the electric current among the PMOS pipe M2.

Because power supply potential band-gap reference generation unit 21 is same current branch with band-gap reference generation unit 22 all with earth potential band-gap reference generation unit 23; Resistance R 20 is equated with resistance R 24; Resistance R 20 equates with the electric current of resistance R 24; Be equal to the electric current sum of PMOS pipe M1 and PMOS pipe M2, therefore, pressure drop V _Bg1With pressure drop V _Bg2Equate that capacitor C 20 is used to be respectively voltage V with capacitor C 21 _Bg1With voltage V _Bg2Filtering.

Because the 3rd operational amplifier A 3 makes the current potential of Node B 20 and Node B 21 equate that the pressure drop of the i.e. pressure drop of resistance R 21, resistance R 22, the pressure drop of diode D1 and resistance R 23 all equate with the series connection pressure drop of diode D2.Order, resistance R 21 equate that with resistance R 22 area of diode D2 is n a times of diode D1, so:

Resistance R 22 electric currents equal resistance R 21 electric currents, can be expressed as:

$I_{R22}=I_{R21}=\frac{V_{D1}}{R21}---\left(1\right)$

The series current of resistance R 23 and diode D21 can be expressed as:

$I_{R23}=\frac{V_{D1}-V_{D2}}{\mathrm{<figure-callout\; id="23"\; label="R"\; filenames="HDA0000112384390000012.png,HDA0000112384390000021.png"\; state="\{\{state\}\}">R</figure-callout>}23}$

(2)

$=\mathrm{Ln}\left(n\right)\frac{\mathrm{kT}}{q}\frac{1}{\mathrm{<figure-callout\; id="23"\; label="R"\; filenames="HDA0000112384390000012.png,HDA0000112384390000021.png"\; state="\{\{state\}\}">R</figure-callout>}23}$

Electric current among the PMOS pipe M1 equals the electric current among the PMOS pipe M2, can be expressed as:

$I_{M1}=I_{M2}=I_{R22}+I_{R23}$

(3)

$=\frac{V_{D1}}{\mathrm{<figure-callout\; id="21"\; label="R"\; filenames="HDA0000112384390000012.png,HDA0000112384390000021.png"\; state="\{\{state\}\}">R</figure-callout>}21}+\mathrm{Ln}\left(n\right)\frac{\mathrm{kT}}{q}\frac{1}{\mathrm{<figure-callout\; id="23"\; label="R"\; filenames="HDA0000112384390000012.png,HDA0000112384390000021.png"\; state="\{\{state\}\}">R</figure-callout>}23}$

Pressure drop V _Bg1With pressure drop V _Bg2Equate, can be expressed as:

$V_{\mathrm{bg}2}={\mathrm{<figure-callout\; id="1"\; label="V\; bg"\; filenames="HDA0000112384390000011.png"\; state="\{\{state\}\}">V</figure-callout>}}_{\mathrm{bg}}=R20\&CenterDot;(I_{M1}+I_{M2})=R20\&CenterDot;2[\frac{V_{D1}}{\mathrm{<figure-callout\; id="21"\; label="R"\; filenames="HDA0000112384390000012.png,HDA0000112384390000021.png"\; state="\{\{state\}\}">R</figure-callout>}21}+L_n\left(n\right)\frac{\mathrm{kT}}{q}\frac{1}{R23}]$

(4)

$=2\frac{R20}{R21}[{\mathrm{<figure-callout\; id="1"\; label="V\; D"\; filenames="HDA0000112384390000011.png"\; state="\{\{state\}\}">V</figure-callout>}}_D+L_n\left(n\right)\frac{\mathrm{kT}}{q}\frac{R21}{R23}]$

Wherein, k is a Boltzmann constant, and T is absolute temperature (K), and q is an electronic charge.

Since in the expression formula (4), pressure drop V _Bg1With pressure drop V _Bg2Expression formula in comprise formula:

And in formula (5), first V _D1For diode D1 forward conduction voltage, has negative temperature characteristic, second

Be the product term of two diode D1, D2 forward conduction voltage difference and resistance ratio R21/R23, have positive temperature characterisitic,, can promptly obtain a bandgap voltage reference that temperature coefficient is extremely low, i.e. voltage V through regulating resistance ratio R21/R23 _Bg1With voltage V _Bg2Be bandgap voltage reference.

Therefore, in expression formula (4), if resistance R 20 is a resistance of the same type with resistance R 21; Then both temperatures coefficient are identical; Can fall approximately, ratio R 20/R21 is stable on temperature, and; Can obtain different relative power supply potential bandgap voltage reference V respectively through regulating the ratio of resistance R 20 and resistance R 21 _Bg1Current potential bandgap voltage reference V relatively _Bg2

Produce the band gap electric currents at the utility model embodiment through two diode semiconductor paths, and on this band gap current branch the directly relative power supply potential bandgap voltage reference of generation and relatively current potential bandgap voltage reference, have following beneficial effect:

(1) circuit is succinct, and current branch is few, and power consumption greatly reduces, and is fit to very much the application of sensitive power consumption;

(2) the circuit elements number of devices is few, satisfies the demand of small size encapsulation, accomplishes that really area is little, cost is low;

(3) circuit progression reduces, and has reduced error source, realizes high precision;

(4) circuit structure symmetry, two bandgap voltage reference high conformities.

Fig. 4 shows the second exemplary circuit structure of the band-gap reference circuit that the utility model one embodiment provides, and for the ease of explanation, only shows the part relevant with the utility model embodiment.

As the utility model one embodiment; Power supply potential band-gap reference generation unit 21 comprises: the 5th diode semiconductor D5, resistance R 25 and capacitor C 22; It is parallelly connected after the 5th diode semiconductor D5 connects with resistance R 25 with capacitor C 22; The anode of the 5th diode semiconductor D5 is connected with an end of capacitor C 22, and its common port is the input end of power supply potential band-gap reference generation unit 21, and resistance R 25 is the output terminal of power supply potential band-gap reference generation unit 21 with the common port of capacitor C 22;

Band-gap reference generation unit 22 comprises: the 3rd switching tube M3, the 4th switching tube M4, four-operational amplifier A4, the 3rd diode semiconductor D3, the 4th diode semiconductor D4, and resistance R 26;

The input end of the 3rd switching tube M3 is connected with the input end of the 4th switching tube M4 and is the input end of band-gap reference generation unit 22 simultaneously; The output terminal of the 3rd switching tube M3 is connected with the reverse input end of four-operational amplifier A4; The output terminal of the 4th switching tube M4 is connected with the positive input of four-operational amplifier A4; The output terminal of four-operational amplifier A4 is connected with the control end of the 3rd switching tube M3, the control end of the 4th switching tube M4 respectively; The output terminal of the 3rd switching tube M3 also is connected with the input end of the 3rd diode semiconductor D3; The output terminal of the 3rd diode semiconductor D3 is the output terminal of band-gap reference generation unit 22; The output terminal of the 4th switching tube M4 also is connected with the input end of the 4th diode semiconductor D4 through resistance R 26, and the output terminal of the 4th diode semiconductor D4 is connected with the output terminal of the 3rd diode semiconductor D3;

Earth potential band-gap reference generation unit 23 comprises: the 6th diode semiconductor D6, resistance R 27 and capacitor C 23; It is parallelly connected after the 6th diode semiconductor D6 connects with resistance R 27 with capacitor C 23; The anode of the 6th diode semiconductor D6 is connected with an end of capacitor C 23; Its common port is the input end of earth potential band-gap reference generation unit 23, and resistance R 27 is the output terminal of earth potential band-gap reference generation unit 23 with the common port of capacitor C 23.

As the utility model one embodiment; The 3rd switching tube M3 and the 4th switching tube M4 all can adopt P type metal-oxide-semiconductor to realize; The source class of this P type metal-oxide-semiconductor is the input end of the 3rd switching tube M3, the 4th switching tube M4; The drain electrode of P type metal-oxide-semiconductor is the output terminal of the 3rd switching tube M3, the 4th switching tube M4, and the grid of P type metal-oxide-semiconductor is the control end of the 3rd switching tube M3, the 4th switching tube M4.

As the utility model one embodiment; The 3rd diode semiconductor D3, the 4th diode semiconductor D4, the 5th diode semiconductor D5, the 6th diode semiconductor D6 all can adopt diode to realize; The anode of this diode is the input end of the 3rd diode semiconductor D3, the 4th diode semiconductor D4, the 5th diode semiconductor D5, the 6th diode semiconductor D6, and the negative electrode of diode is the output terminal of the 3rd diode semiconductor D3, the 4th diode semiconductor D4, the 5th diode semiconductor D5, the 6th diode semiconductor D6.

As the utility model one embodiment, the 3rd diode semiconductor D3, the 4th diode semiconductor D4, the 5th diode semiconductor D5, the 6th diode semiconductor D6 also can adopt transistor to realize.

Preferably, the 3rd diode semiconductor D3, the 4th diode semiconductor D4, the 5th diode semiconductor D5, the 6th diode semiconductor D6 all can adopt vertical bipolar transistor to realize;

The 3rd diode semiconductor D3, the 4th diode semiconductor D4, the 5th diode semiconductor D5, the 6th diode semiconductor D6 also can adopt the MOS field effect transistor that works in accurate threshold zone to realize.

In the utility model embodiment; PMOS pipe M3 and PMOS pipe M4 are measure-alike; Constitute current mirror, the electric current that promptly flows through PMOS pipe M3 and PMOS pipe M4 equates that four-operational amplifier A4 equates the voltage of its positive input and reverse input end; The electric current of diode D3 equals the electric current of PMOS pipe M3, and resistance R 26 equates with the electric current of PMOS pipe M4 with the electric current of diode D4 series connection.

Because power supply potential band-gap reference generation unit 21 is same current branch with band-gap reference generation unit 22 all with earth potential band-gap reference generation unit 23; Resistance R 25 is equated with resistance R 27; Resistance R 25 equates with the electric current of resistance R 27, is equal to the electric current sum of PMOS pipe M3 and PMOS pipe M4, is the band-gap reference electric current that band-gap reference generation unit 22 produces; The area of setting diode D4 is n a times of diode D3, so:

Electric current among the PMOS pipe M3 equals the electric current among the PMOS pipe M4, can be expressed as:

$I_{M3}=I_{M4}=\frac{V_{D3}-V_{D4}}{R26}=\mathrm{Ln}\left(n\right)\frac{\mathrm{kT}}{q}\frac{1}{R26}---\left(6\right)$

Pressure drop V _Bg3With pressure drop V _Bg4Equate, can be expressed as:

$V_{\mathrm{bg}3}={\mathrm{<figure-callout\; id="4"\; label="V\; bg"\; filenames="HDA0000112384390000031.png"\; state="\{\{state\}\}">V</figure-callout>}}_{\mathrm{bg}}=V_{D6}+(I_{M3}+I_{M4})R27=V_{D6}+2\mathrm{Ln}\left(n\right)\frac{\mathrm{kT}}{q}\frac{R27}{R26}---\left(7\right)$

Wherein, k is a Boltzmann constant, and T is absolute temperature (K), and q is an electronic charge.

Because first V in the expression formula (7) _D6For having negative temperature characteristic, second Have positive temperature characterisitic,, can obtain the extremely low bandgap voltage reference V of temperature coefficient through regulating resistance ratio R27/R26 _Bg3And V _Bg4, promptly relative power supply potential bandgap voltage reference V _Bg3Current potential bandgap voltage reference V relatively _Bg4, capacitor C 22 is used to be respectively relative power supply potential bandgap voltage reference V with capacitor C 23 _Bg3Current potential bandgap voltage reference V relatively _Bg4Filtering.

The utility model embodiment produces the band gap electric currents through two diode semiconductor paths, and on this band gap current branch the directly relative power supply potential bandgap voltage reference of generation and relatively current potential bandgap voltage reference, have following beneficial effect:

(1) circuit is succinct, and current branch is few, and power consumption greatly reduces, and is fit to very much the application of sensitive power consumption;

(2) the circuit elements number of devices is few, satisfies the demand of small size encapsulation, accomplishes that really area is little, cost is low;

(3) circuit progression reduces, and has reduced error source, realizes high precision;

(4) circuit structure symmetry, two bandgap voltage reference high conformities.

More than be merely the preferred embodiment of the utility model,, any modification of being done within all spirit at the utility model and the principle, be equal to and replace and improvement etc., all should be included within the protection domain of the utility model not in order to restriction the utility model.

Claims (10)

1. a band-gap reference circuit is characterized in that, said band-gap reference circuit comprises:

Produce the band-gap reference generation unit of band gap electric current through two diode semiconductor paths;

According to said band gap electric current and supply voltage; On said band gap current branch, generate the power supply potential band-gap reference generation unit of relative power supply potential bandgap voltage reference; The input end of said power supply potential band-gap reference generation unit is connected with supply voltage, and the output terminal of said power supply potential band-gap reference generation unit is connected with the input end of said band-gap reference generation unit;

According to said band gap electric current and earth potential; On said band gap current branch, generate the earth potential band-gap reference generation unit of current potential bandgap voltage reference relatively; The input end of said earth potential band-gap reference generation unit is connected with the output terminal of said band-gap reference generation unit, and the output terminal of said earth potential band-gap reference generation unit is connected with ground.

2. band-gap reference circuit as claimed in claim 1; It is characterized in that said band-gap reference generation unit comprises: first switching tube, second switch pipe, the 3rd operational amplifier, first diode semiconductor, second diode semiconductor, resistance R 21, resistance R 22 and resistance R 23;

The input end of said first switching tube is connected with the input end of said second switch pipe and is the input end of said band-gap reference generation unit simultaneously; Said first output end of switching tube is connected with the reverse input end of said the 3rd operational amplifier; The output terminal of said second switch pipe is connected with the positive input of said the 3rd operational amplifier; The output terminal of said the 3rd operational amplifier is connected with the control end of said first control end of switching tube, said second switch pipe respectively; Said first output end of switching tube also is connected with the input end of said first diode semiconductor; The output terminal of said first diode semiconductor is the output terminal of said band-gap reference generation unit; Said resistance R 21 is parallelly connected with said first diode semiconductor, and the output terminal of said second switch pipe also is connected with the input end of said second diode semiconductor through resistance R 23, and the output terminal of said second diode semiconductor is connected with the output terminal of said first diode semiconductor; One end of said resistance R 22 is connected with the output terminal of said second switch pipe, and the other end of said resistance R 22 is connected with the output terminal of said second diode semiconductor;

Power supply potential band-gap reference generation unit comprises: resistance R 20 and capacitor C 20; Said resistance R 20 is parallelly connected with said capacitor C 20; The one of which common port is the input end of said power supply potential band-gap reference generation unit, and another common port is the output terminal of said power supply potential band-gap reference generation unit;

Earth potential band-gap reference generation unit comprises: resistance R 24 and capacitor C 21; Said resistance R 24 is parallelly connected with said capacitor C 21; The one of which common port is the input end of said earth potential band-gap reference generation unit, and another common port is the output terminal of said earth potential band-gap reference generation unit.

3. band-gap reference circuit as claimed in claim 2; It is characterized in that; Said first switching tube and said second switch pipe are P type metal-oxide-semiconductor; The source class of said P type metal-oxide-semiconductor is the input end of said first switching tube, said second switch pipe, and the drain electrode of said P type metal-oxide-semiconductor is the output terminal of said first switching tube, said second switch pipe, and the grid of said P type metal-oxide-semiconductor is the control end of said first switching tube, said second switch pipe.

4. band-gap reference circuit as claimed in claim 2 is characterized in that, said first diode semiconductor and said second diode semiconductor are diode; Or

Said first diode semiconductor and said second diode semiconductor are transistor.

5. band-gap reference circuit as claimed in claim 2 is characterized in that, said first diode semiconductor and said second diode semiconductor are vertical bipolar transistor; Or

Said first diode semiconductor and said second diode semiconductor are the MOS field effect transistor that works in accurate threshold zone.

6. band-gap reference circuit as claimed in claim 1 is characterized in that, said band-gap reference generation unit comprises: the 3rd switching tube, the 4th switching tube, four-operational amplifier, the 3rd diode semiconductor, the 4th diode semiconductor, and resistance R 26;

The input end of said the 3rd switching tube is connected with the input end of said the 4th switching tube and is the input end of said band-gap reference generation unit simultaneously; Said the 3rd output end of switching tube is connected with the reverse input end of said four-operational amplifier; Said the 4th output end of switching tube is connected with the positive input of said four-operational amplifier; The output terminal of said four-operational amplifier is connected with said the 3rd control end of switching tube, said the 4th control end of switching tube respectively; Said the 3rd output end of switching tube also is connected with the input end of said the 3rd diode semiconductor; The output terminal of said the 3rd diode semiconductor is the output terminal of said band-gap reference generation unit; Said the 4th output end of switching tube also is connected with the input end of said the 4th diode semiconductor through resistance R 26, and the output terminal of said the 4th diode semiconductor is connected with the output terminal of said the 3rd diode semiconductor;

Power supply potential band-gap reference generation unit comprises: the 5th diode semiconductor, resistance R 25 and capacitor C 22; Connect with said resistance R 25 back and said capacitor C 22 of said the 5th diode semiconductor is parallelly connected; The anode of said the 5th diode semiconductor D5 is connected with an end of said capacitor C 22; Its common port is the input end of said power supply potential band-gap reference generation unit, and said resistance R 25 is the output terminal of said power supply potential band-gap reference generation unit with the common port of said capacitor C 22;

Earth potential band-gap reference generation unit comprises: the 6th diode semiconductor, resistance R 27 and capacitor C 23; Connect with said resistance R 27 back and said capacitor C 23 of said the 6th diode semiconductor is parallelly connected; The anode of said the 6th diode semiconductor is connected with an end of said capacitor C 23; Its common port is the input end of said earth potential band-gap reference generation unit, and said resistance R 27 is the output terminal of said earth potential band-gap reference generation unit with the common port of said capacitor C 23.

7. band-gap reference circuit as claimed in claim 6; It is characterized in that; Said the 3rd switching tube and said the 4th switching tube are P type metal-oxide-semiconductor; The source class of said P type metal-oxide-semiconductor is the input end of said the 3rd switching tube, said the 4th switching tube, and the drain electrode of said P type metal-oxide-semiconductor is said the 3rd switching tube, said the 4th output end of switching tube, and the grid of said P type metal-oxide-semiconductor is said the 3rd switching tube, said the 4th control end of switching tube.

8. band-gap reference circuit as claimed in claim 6 is characterized in that, said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are diode; Or

Said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are transistor; Or

Said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are vertical bipolar transistor; Or

Said the 3rd diode semiconductor, said the 4th diode semiconductor, the 5th diode semiconductor, the 6th diode semiconductor are the MOS field effect transistor that works in accurate threshold zone.

9. a power protecting circuit is characterized in that, the band-gap reference circuit in the said power protecting circuit is like each described band-gap reference circuit of claim 1 to 8.

10. a power supply is characterized in that, the power protecting circuit in the said power supply is a power protecting circuit as claimed in claim 9.

Images