CN1881785B - DC voltage bias circuit and its application in integrated circuit - Google Patents

Abstract

The invention relates to a direct-current voltage bias circuit, which is characterized in that: it is formed by three resistances serially connected between the power supply and the ground terminal and the filter capacitors connected between two resistances that near the power supply and the between the ground points, wherein the resistance near the power supply is larger than the sum of another two resistances, and when power supply is not higher than two times of output voltage, the middle resistance can be eliminated. The invention has the advantages that: it uses divided resistances to supply the bias voltage at any level; and the output bias voltage will change along the change of direct-current voltage, but not change along the temperature. The invention has simple structure, low power consumption, small volume, low cost, and better PSRR property.

Description

A kind of DC voltage bias circuit and the application in integrated circuit thereof

(1) technical field:

The present invention relates to a kind of application of circuit, particularly a kind of DC voltage bias circuit and the application in integrated circuit thereof.

(2) background technology:

At present, in integrated circuit (IC) design, a lot of circuit (for example operational amplifier, comparator) all need DC voltage bias circuit, are used to provide the direct current biasing working point.Therefore the quality that designs in integrated circuit (IC) design of voltage offset electric circuit directly influences the performance of circuit.

Usually dc bias circuit adopts Band Gap structure mostly, and structure as shown in Figure 1.The principle of Bandgap is to utilize the counteracting of Positive and Negative Coefficient Temperature, thereby produces the reference voltage of 0 temperature coefficient.This structure is usually by an operational amplifier, and several triodes, resistance are formed.Its advantage is that output voltage does not change with the variation of temperature, supply voltage, has good PSRR (supply-voltage rejection ratio) performance.But Band Gap also has a lot of significant disadvantages:

1, along with the continuous development of integrated circuit submicrometer processing, the metal-oxide-semiconductor size constantly reduces, supply voltage constantly reduces minimum can reaching below the 1.2V (as shown in Figure 1), because the cut-in voltage of triode is usually about 0.7V, therefore only be left to leave metal-oxide-semiconductor work in the operational amplifier for less than the 0.5V voltage margin, make the metal-oxide-semiconductor of the interior operational amplifier of Band Gap be difficult to operate as normal in the zone of saturation, therefore under very low supply voltage situation, Band Gaps can't operate as normal.

2, owing to the restriction of circuit structure, the Band Gap of structure can only provide the bias voltage greater than 0.7V usually.

3, Band Gap obtains the structure that the cost of fine performance is a complexity, uses a lot of resistance, and triode, therefore needs very big area and power consumption.

4, because the complexity of structure causes reliability very poor, precision is difficult on the contrary guarantee that the method for therefore having introduced a lot of complexity is used for adjusting precision, technology such as Trimming for example, thus increased the production cost of circuit.

5, the bias voltage that provides of Band Gap is not with mains voltage variations, but in a lot of circuit, if the biased electrical pressure energy changes along with mains voltage variations, can compensate some negative effects that cause owing to mains voltage variations on the contrary.

In sum, the use of Band Gap circuit has significant limitation and significant disadvantages.At this moment, seek a kind of DC voltage bias circuit of dc offset voltage that can effectively provide and become extremely important.

(3) summary of the invention:

The object of the present invention is to provide a kind of DC voltage bias circuit and the application in integrated circuit thereof, it has overcome the limitation and the shortcoming of dc bias circuit of the Band Gap structure of existing common employing, is the very strong novel optimization circuit design of a kind of practicality.

Technical scheme of the present invention: a kind of DC voltage bias circuit, it is characterized in that it by be connected two to three resistance of being connected with between power voltage terminal and the earth terminal, be connected near between two resistance of power voltage terminal and the filter capacitor between earth point form; It is that resistance near the resistance of power voltage terminal is two other resistance sum that the resistance of said three resistance is closed, and when satisfying supply voltage and be not more than the output voltage of twice, the resistance in omission centre position.

A kind of application of DC voltage bias circuit, the operational environment that it is characterized in that it are the integrated circuit of common process, the integrated circuit of submicrometer processing and the integrated circuit of deep submicron process.

A kind of application process of DC voltage bias circuit of integrated circuit is characterized in that it may further comprise the steps:

1. adopt the form of electric resistance partial pressure directly to provide dc offset voltage to circuit

$V_{\mathrm{ref}}=V_{\mathrm{DD}}\·\frac{R_2+R_3}{R_1+R_2+R_3};$

2. in order to improve the PSRR performance, increase bypass filter capacitor C, obtain

$\mathrm{Vref}\left(S\right)=\mathrm{VDD}\left(S\right)\·\frac{R2+R3}{R1+\frac{1}{\mathrm{SC}+\frac{1}{R2+R3}}},$

Arrangement can obtain

R=R wherein ₁+ R ₂+ R ₃

3. in order to make Vref (s) obtain minimum value when the high frequency, can draw R ₁, R ₂, R ₃Relation: (1) works as V _Ref＜V _DD/ 2 o'clock, R ₁=R ₂+ R ₃(2) work as V _Ref〉=V _DD/ 2 o'clock, R ₂=0;

4. test the temperature characterisitic of this circuit: because resistance varies with temperature characteristic and is:

TC wherein ₁, TC ₂Be the temperature coefficient and the secondary temperature coefficient of resistance, R ₀Be the resistance of resistance when 25 spend, the temperature characterisitic that can export is thus:

R wherein ₀=R ₁₀+ R ₂₀+ R ₃₀, and have Be that output voltage is temperature independent.

Operation principle of the present invention: because the quality that voltage offset electric circuit designs in integrated circuit (IC) design directly has influence on the performance of circuit itself, therefore, it is that integrated circuit (as operational amplifier, comparator) provides dc offset voltage that the present invention adopts the mode of electric resistance partial pressure, simultaneously, increase the bypass filter capacitor and eliminated the supply voltage The noise, improved the stability of output voltage, promptly finished the function of traditional complicated voltage offset electric circuit, and improved the service behaviour of integrated circuit by the use simple circuit configuration.

Superiority of the present invention and characteristics are: 1, can be operated under the very low supply voltage, especially supply voltage is usually under the situation less than 1.5V in present most advanced world submicrometer processing, and advantage is more obvious; 2, owing to adopt the electric resistance partial pressure form, therefore can easily solve the low supply voltage problem, the bias voltage of any level can be provided; 3 output offset voltages correspondingly change along with the variation of supply voltage, and when the DC level of supply voltage changed, output offset voltage changed corresponding multiple immediately; 4, bias voltage does not vary with temperature; 5, simple in structure, low-power consumption, reliability height; 6, area is little, is convenient to integratedly, reduces cost; 7, good PSRR (Power Supply Rejection Ratio supply-voltage rejection ratio) performance; 8, can play the effect of compensation to the variation of some circuit performance that causes owing to the variation of supply voltage.

(4) description of drawings:

Accompanying drawing 1 is existing Bandgap circuit structure diagram.

(wherein, Fig. 2-a is V for the voltage offset electric circuit structure chart of two kinds of situations in the related a kind of DC voltage bias circuit of the present invention for accompanying drawing 2 _Ref＜V _DD/ 2, R ₁=R ₂+ R ₃Fig. 2-b is V _Ref〉=V _DD/ 2).

Accompanying drawing 3 provides the DC voltage bias circuit structure chart (seeing embodiment 1) of bias voltage for the rim detection module in RF application for the related a kind of DC voltage bias circuit of the present invention.

Accompanying drawing 4 is used to produce the circuit structure diagram (seeing embodiment 2) of reference voltage in the level detection field for the related a kind of DC voltage bias circuit of the present invention.

Accompanying drawing 5 provides the circuit structure diagram (seeing embodiment 3) of bias voltage for active filter for the related a kind of DC voltage bias circuit of the present invention.

The circuit structure diagram (seeing embodiment 4) that accompanying drawing 6 provides quiescent biasing to be used to produce reference current for the related a kind of DC voltage bias circuit of the present invention.

Wherein: R ₁, R ₂, R ₃Be divider resistance, C is a filter capacitor, V _DDBe supply voltage, V _RefBe the output offset reference voltage.

(5) embodiment:

Embodiment 1: a kind of DC voltage bias circuit (is seen Fig. 2-a), it is characterized in that it is three resistance R that are connected with between power voltage terminal and the earth terminal by being connected ₁, R ₂And R ₃, be connected near supply voltage V _DDBetween two resistance of end and the filter capacitor C between earth point form; It is near supply voltage V that the resistance of said three resistance is closed _DDThe resistance R of end ₁Resistance be two other resistance R ₂And R ₃The resistance sum, and when satisfying supply voltage V _DDBe not more than the output voltage V of twice _RefThe time, omit the resistance R in centre position ₂(see Fig. 2-b).

A kind of application of DC voltage bias circuit, the operational environment that it is characterized in that it is for providing the bias voltage (see figure 3) for the rim detection module in RF application.

A kind of application process of DC voltage bias circuit of integrated circuit is characterized in that it may further comprise the steps:

1. adopt the form of electric resistance partial pressure directly to provide dc offset voltage to circuit

$V_{\mathrm{ref}}=V_{\mathrm{DD}}\·\frac{R_2+R_3}{R_1+R_2+R_3};$

2. in order to improve the PSRR performance, increase bypass filter capacitor C, obtain

$\mathrm{Vref}\left(S\right)=\mathrm{VDD}\left(S\right)\·\frac{R2+R3}{R1+\frac{1}{\mathrm{SC}+\frac{1}{R2+R3}}}$

Arrangement can obtain R=R wherein ₁+ R ₂+ R ₃

3. in order to make V _{Ref (s)}When high frequency, obtain minimum value, can draw R ₁, R ₂, R ₃Relation:

(1) works as V _Ref＜V _DD/ 2 o'clock, R ₁=R ₂+ R ₃(2) work as V _Ref〉=V _DD/ 2 o'clock, R ₂=0;

4. test the temperature characterisitic of this circuit: because resistance varies with temperature characteristic and is:

TC wherein ₁, TC ₂Be the temperature coefficient and the secondary temperature coefficient of resistance, R ₀Be the resistance of resistance when 25 spend, the temperature characterisitic that can export is thus:

R wherein ₀=R ₁₀+ R ₂₀+ R ₃₀, and have Be that output voltage is temperature independent.

Embodiment 2: a kind of DC voltage bias circuit (is seen Fig. 2-a), it is characterized in that it is by being connected supply voltage V _DDThree resistance R that are connected with between end and the earth terminal ₁, R ₂And R ₃, be connected near supply voltage V _DDBetween two resistance of end and the filter capacitor C between earth point form; It is near supply voltage V that the resistance of said three resistance is closed _DDThe resistance R of end ₁Resistance be two other resistance R ₂And R ₃The resistance sum, and when satisfying supply voltage V _DDBe not more than the output voltage V of twice _RefThe time, omit the resistance R in centre position ₂(see Fig. 2-b).

A kind of application of DC voltage bias circuit is characterized in that its operational environment is used to produce the reference voltage (see figure 4) in the level detection field.

A kind of application process of DC voltage bias circuit of integrated circuit is characterized in that it may further comprise the steps:

1. adopt the form of electric resistance partial pressure directly to provide dc offset voltage to circuit

$V_{\mathrm{ref}}=V_{\mathrm{DD}}\·\frac{R_2+R_3}{R_1+R_2+R_3};$

2. in order to improve the PSRR performance, increase bypass filter capacitor C, obtain

$\mathrm{Vref}\left(S\right)=\mathrm{VDD}\left(S\right)\·\frac{R_2+R_3}{R1+\frac{1}{\mathrm{SC}+\frac{1}{R2+R3}}},$

Arrangement can obtain

R=R wherein ₁+ R ₂+ R ₃

3. in order to make V _{Ref (s)}When high frequency, obtain minimum value, can draw R ₁, R ₂, R ₃Relation:

(1) works as V _Ref＜V _DD/ 2 o'clock, R ₁=R ₂+ R ₃(2) work as V _Ref〉=V _DD/ 2 o'clock, R ₂=0;

4. test the temperature characterisitic of this circuit: because resistance varies with temperature characteristic and is:

TC wherein ₁, TC ₂Be the temperature coefficient and the secondary temperature coefficient of resistance, R ₀Be the resistance of resistance when 25 spend, the temperature characterisitic that can export is thus:

R wherein ₀=R ₁₀+ R ₂₀+ R ₃₀, and have

Be that output voltage is temperature independent.

Embodiment 3: a kind of DC voltage bias circuit (is seen Fig. 2-a), it is characterized in that it is by being connected supply voltage V _DDThree resistance R that are connected with between end and the earth terminal ₁, R ₂And R ₃, be connected near supply voltage V _DDBetween two resistance of end and the filter capacitor C between earth point form; It is near supply voltage V that the resistance of said three resistance is closed _DDThe resistance R of end ₁Resistance be two other resistance R ₂And R ₃The resistance sum, and when satisfying supply voltage V _DDBe not more than the output voltage V of twice _RefThe time, omit the resistance R in centre position ₂(see Fig. 2-b).

A kind of application of DC voltage bias circuit is characterized in that its operational environment provides the bias voltage (see figure 5) for active filter.

A kind of application process of DC voltage bias circuit of integrated circuit is characterized in that it may further comprise the steps:

1. adopt the form of electric resistance partial pressure directly to provide dc offset voltage to circuit

$V_{\mathrm{ref}}=V_{\mathrm{DD}}\·\frac{R_2+R_3}{R_1+R_2+R_3};$

2. in order to improve the PSRR performance, increase bypass filter capacitor C, obtain

$\mathrm{Vref}\left(S\right)=\mathrm{VDD}\left(S\right)\·\frac{R2+R3}{R1+\frac{1}{\mathrm{SC}+\frac{1}{R2+R3}}},$

Arrangement can obtain

R=R wherein ₁+ R ₂+ R ₃

3. in order to make V _{Ref (s)}When high frequency, obtain minimum value, can draw R ₁, R ₂, R ₃Relation:

(1) works as V _Ref＜V _DD/ 2 o'clock, R ₁=R ₂+ R ₃(2) work as V _Ref〉=V _DD/ 2 o'clock, R ₂=0;

4. test the temperature characterisitic of this circuit: because resistance varies with temperature characteristic and is:

TC wherein ₁, TC ₂Be the temperature coefficient and the secondary temperature coefficient of resistance, R ₀Be the resistance of resistance when 25 spend, the temperature characterisitic that can export is thus:

R wherein ₀=R ₁₀+ R ₂₀+ R ₃₀, and have

Be that output voltage is temperature independent.

Embodiment 4: a kind of DC voltage bias circuit (is seen Fig. 2-a), it is characterized in that it is by being connected supply voltage V _DDThree resistance R that are connected with between end and the earth terminal ₁, R ₂And R ₃, be connected near supply voltage V _DDBetween two resistance of end and the filter capacitor C between earth point form; It is near supply voltage V that the resistance of said three resistance is closed _DDThe resistance R of end ₁Resistance be two other resistance R ₂And R ₃The resistance sum, and when satisfying supply voltage V _DDBe not more than the output voltage V of twice _RefThe time, omit the resistance R in centre position ₂(see Fig. 2-b).

A kind of application of DC voltage bias circuit is characterized in that its operational environment is used to produce the reference current (see figure 6) for various modules provide quiescent biasing.

A kind of application process of DC voltage bias circuit of integrated circuit is characterized in that it may further comprise the steps:

1. adopt the form of electric resistance partial pressure directly to provide dc offset voltage to circuit

$V_{\mathrm{ref}}=V_{\mathrm{DD}}\·\frac{R_2+R_3}{R_1+R_2+R_3};$

2. in order to improve the PSRR performance, increase bypass filter capacitor C, obtain

$\mathrm{Vref}\left(S\right)=\mathrm{VDD}\left(S\right)\·\frac{R2+R3}{R1+\frac{1}{\mathrm{SC}+\frac{1}{R2+R3}}},$

Arrangement can obtain R=R wherein ₁+ R ₂+ R ₃

3. in order to make V _{Ref (s)}When high frequency, obtain minimum value, can draw R ₁, R ₂, R ₃Relation:

(1) works as V _Ref＜V _DD/ 2 o'clock, R ₁=R ₂+ R ₃(2) work as V _Ref〉=V _DD/ 2 o'clock, R ₂=0;

4. test the temperature characterisitic of this circuit: because resistance varies with temperature characteristic and is:

TC wherein ₁, TC ₂Be the temperature coefficient and the secondary temperature coefficient of resistance, R ₀Be the resistance of resistance when 25 spend, the temperature characterisitic that can export is thus:

R wherein ₀=R ₁₀+ R ₂₀+ R ₃₀, and have

Be that output voltage is temperature independent.

Claims (4)

1. DC voltage bias circuit, it is characterized in that it by be connected three resistance being connected with between power voltage terminal and the earth terminal, be connected near between two resistance of power voltage terminal and the filter capacitor between earth point form; It is that resistance near the resistance of power voltage terminal is two other resistance sum that the resistance of said three resistance is closed, and when satisfying supply voltage and be not more than the output voltage of twice, the resistance in omission centre position.

2. according to the said a kind of DC voltage bias circuit of claim 1, it is characterized in that it can be applied to the integrated circuit of the integrated circuit of common process, submicrometer processing and the integrated circuit of deep submicron process.

3. according to claim 1 or 2 said a kind of DC voltage bias circuits, the operational environment that it is characterized in that DC voltage bias circuit can be bias voltage is provided, is used to produce reference voltage in the level detection field, bias voltage is provided or provides quiescent biasing to be used to produce reference current for active filter for the rim detection module in RF application.

4. the application process of the DC voltage bias circuit of an integrated circuit is characterized in that it may further comprise the steps:

1. adopt the form of electric resistance partial pressure directly to provide dc offset voltage to circuit

$V_{\mathrm{ref}}=V_{\mathrm{DD}}\·\frac{R_2+R_2}{R_1+R_2+R_3};$

2. in order to improve the PSRR performance, increase bypass filter capacitor C, obtain

$\mathrm{Vref}\left(S\right)=\mathrm{VDD}\left(S\right)\·\frac{R2+R3}{R1+\frac{1}{\mathrm{SC}+\frac{1}{R2+R3}}},$

Arrangement can obtain

R=R wherein ₁+ R ₂+ R ₃

3. in order to make V _{Ref (s)}When high frequency, obtain minimum value, can draw R ₁, R ₂, R ₃Relation: (1) works as V _Ref＜V _DD/ 2 o'clock, R ₁=R ₂+ R ₃(2) work as V _Ref〉=V _DD/ 2 o'clock, R ₂=0;

4. test the temperature characterisitic of this circuit: because resistance varies with temperature characteristic and is:

TC wherein ₁, TC ₂Be the temperature coefficient and the secondary temperature coefficient of resistance, R ₀Be the resistance of resistance when 25 spend, the temperature characterisitic that can export is thus:

R wherein ₀=R ₁₀+ R ₂₀+ R ₃₀, and have Be that output voltage is temperature independent.

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