CN115793769B - Band gap reference sliding temperature compensation circuit and method - Google Patents
Band gap reference sliding temperature compensation circuit and method Download PDFInfo
- Publication number
- CN115793769B CN115793769B CN202310043501.7A CN202310043501A CN115793769B CN 115793769 B CN115793769 B CN 115793769B CN 202310043501 A CN202310043501 A CN 202310043501A CN 115793769 B CN115793769 B CN 115793769B
- Authority
- CN
- China
- Prior art keywords
- array
- temperature coefficient
- transistor
- current
- circuit
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000009966 trimming Methods 0.000 claims abstract description 34
- 230000011664 signaling Effects 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 15
- 238000004088 simulation Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000006978 adaptation Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
Images
Landscapes
- Control Of Electrical Variables (AREA)
Abstract
The embodiment of the application provides a band gap reference sliding temperature compensation circuit and a method, wherein the circuit comprises a band gap reference circuit and a trimming circuit, and the trimming circuit is configured to: comparing the magnitude relation of n paths of positive temperature coefficient currents and n paths of zero temperature coefficient currents of the band gap reference circuit, and controlling the proportion of controllable resistors in the band gap reference circuit according to the comparison result, wherein n is an integer larger than 0. The compensation scheme of the band gap reference in the related technology is complex in circuit structure and does not have universality.
Description
Technical Field
The application relates to the technical field of microelectronics, in particular to a band gap reference sliding temperature compensation circuit and a band gap reference sliding temperature compensation method.
Background
The band gap reference is a circuit structure commonly used in an analog integrated circuit, can output relatively stable reference voltage under the conditions of process, voltage and temperature change, and is widely applied to the fields of signal chains, power management and the like.
The temperature coefficient of the bandgap reference is one of the most important indexes, and the bandgap reference output fluctuates with temperature under the influence of non-ideal factors of the device. In order to make the bandgap reference output less affected by temperature, i.e., to realize a bandgap reference with a smaller temperature coefficient, a compensation method thereof has been a widely focused field. The common temperature compensation scheme mostly performs temperature coefficient cancellation, namely, generates a voltage or current with a temperature coefficient opposite to the band gap reference high-order temperature coefficient, and cancels the temperature coefficient in a superposition mode. The scheme circuit for performing superposition compensation by using the high-order circuit is complex in realization, and different bandgap reference structures need to adopt different superposition schemes, so that universality is not realized.
Aiming at the problems that the circuit structure of a compensation scheme of the band gap reference is complex and has no universality in the related technology, no effective solution exists at present.
Disclosure of Invention
The embodiment of the application provides a band-gap reference sliding temperature compensation circuit and a band-gap reference sliding temperature compensation method, which are used for solving the problems that a band-gap reference compensation scheme in the related art is complex in circuit structure and not universal.
In one embodiment of the present application, a bandgap reference sliding temperature compensation circuit is provided, including a bandgap reference circuit and a trimming circuit, wherein the bandgap reference circuit includes a controllable resistor therein, and the trimming circuit includes: the zero temperature coefficient current array comprises n paths of zero temperature coefficient currents, and the zero temperature coefficient current array corresponds to n paths of positive temperature coefficient currents of the band gap reference circuit one by one, wherein n is an integer greater than 0; the current comparator array comprises n current comparators and is configured to compare the magnitude relation between the positive temperature coefficient current and the zero temperature coefficient current of the band gap reference circuit corresponding to each path; the switch array comprises m switches, m groups of controllable resistors connected with the band gap reference circuit are respectively controlled, and the switch array is configured to control the on-off of the m groups of controllable resistors according to the comparison result output by the current comparator array, wherein m is an integer greater than 0; the trimming circuit is configured to: comparing the magnitude relation between n paths of positive temperature coefficient currents of the band-gap reference circuit and n paths of zero temperature coefficient currents externally connected, and controlling the proportion of controllable resistors in the band-gap reference circuit according to the comparison result.
In an embodiment, the trimming circuit further comprises: and the decoder is respectively connected with the current comparator array and the switch array, and is configured to convert the thermometer code output by the current comparator array into a binary code and control the on and off of the switch array.
In one embodiment, the bandgap reference circuit includes: first MOS tube, second MOS tube, first transistor, n q The MOS transistor comprises a first MOS transistor, a second MOS transistor, a first resistor, a second resistor and m groups of controllable resistors, wherein the source electrode of the first MOS transistor is connected with a power supply, the grid electrode of the first MOS transistor is connected with the grid electrode and the drain electrode of the second MOS transistor, the drain electrode of the first MOS transistor is connected with the collector electrode of the second transistor, the emitter electrode of the second transistor is connected with one end of the first resistor, the other end of the first resistor and the emitter electrode of the first transistor are both connected with the second resistor, and the m groups of controllable resistors are connected with the second resistor in series; the trimming circuit comprises: the MOS transistor comprises a third MOS transistor array, a zero temperature coefficient current array, a current comparator array, a decoder and a switch array, wherein the source electrode of the third MOS transistor array is connected with a power supply, the grid electrode of the third MOS transistor array is connected with the drain electrode of the second MOS transistor, the drain electrode of the third MOS transistor array is respectively connected with the current comparator array, the third MOS transistor array is used for generating n paths of positive temperature coefficient currents, the zero temperature coefficient current array is connected with the current comparator array, the current comparator array is connected with the decoder, the decoder is connected with the switch array, and the switch array is respectively controlled and connected with the switch arraym groups of controllable resistors.
In one embodiment, the bandgap reference circuit includes: amplifier OPAMP, fourth MOS tube, fifth MOS tube, sixth MOS tube, third transistor, n q The transistor comprises a fourth transistor, a fifth transistor, a third resistor, a fourth resistor and m groups of controllable resistors which are connected in parallel, wherein sources of the fourth MOS transistor, the fifth MOS transistor and the sixth MOS transistor are all connected with a power supply, grids of the fourth MOS transistor, the fifth MOS transistor and the sixth MOS transistor are mutually connected, an output end of an amplifier OPAMP is connected with the grid of the fourth MOS transistor, a negative input end of the amplifier OPAMP is connected with an emitter of the third transistor and a drain of the fourth MOS transistor, a positive input end of the amplifier OPAMP is sequentially connected with the drain of the third resistor and the drain of the fifth MOS transistor, the other end of the third resistor is connected with the emitter of the fourth transistor, the drain of the sixth MOS transistor is sequentially connected with the fourth resistor and the fifth transistor, m groups of controllable resistors are serially connected between the fourth resistor and the fifth transistor, and a base and a collector of the fifth transistor are all grounded; the trimming circuit comprises: the MOS transistor array comprises a seventh MOS transistor array, a zero temperature coefficient current array, a current comparator array, a decoder and a switch array, wherein sources of the seventh MOS transistor array are connected with a power supply, gates of the seventh MOS transistor array are connected with gates of the sixth MOS transistor, drains of the seventh MOS transistor array are respectively connected with the current comparator array, the seventh MOS transistor array is used for generating n paths of positive temperature coefficient currents, the zero temperature coefficient current array is connected with the current comparator array, the current comparator array is connected with the decoder, the decoder is connected with the switch array, and the switch array is respectively connected with m groups of controllable resistors in a control mode.
In one embodiment, the n-way positive temperature coefficient current
To->
The magnitudes of the n zero temperature coefficient currents satisfy the following formula:
。
In one embodiment of the present application, a bandgap reference compensation method is also presented, including: comparing the magnitude relation of n paths of positive temperature coefficient currents and n paths of zero temperature coefficient currents of the band gap reference circuit to obtain a comparison result of each path, wherein the n paths of zero temperature coefficient currents are in one-to-one correspondence with the n paths of positive temperature coefficient currents of the band gap reference circuit, and n is an integer larger than 0; and controlling the proportion of controllable resistance in the band gap reference circuit according to the comparison result.
In an embodiment, the comparing the magnitude relation between the n positive temperature coefficient currents and the n zero temperature coefficient currents of the bandgap reference circuit to obtain the comparison result of each path includes: each group is provided with
And->
Respectively connected to two ends of the nth current comparator, outputting thermometer codes through the current comparator array, wherein +_>
To->
For n equal positive temperature coefficient currents in the bandgap reference circuit +.>
For zero temperature coefficient current, each path of current satisfies +.>
The method comprises the steps of carrying out a first treatment on the surface of the Control switch array by the value of the thermometer code>
Wherein the switch array is turned on and off
For controlling m groups of controllable resistances +.>
Is provided.
In one embodiment, the switch array is controlled by the value of the thermometer code
Is turned on and off, comprising: when->
Is greater than->
When the nth bit output of the current comparator array is 1; converting thermometer codes output by the current comparator array into binary signaling through a decoder; controlling the switch array by the binary signaling
Is turned on and off, wherein->
。
According to the band gap reference sliding temperature compensation circuit and the compensation method, the trimming circuit is used for comparing the magnitude relation between n paths of positive temperature coefficient currents and n paths of zero temperature coefficient currents of the band gap reference circuit, and controlling the proportion of controllable resistors in the band gap reference circuit according to the comparison result, so that the problems that the band gap reference compensation scheme in the related art is complex in circuit structure and not universal are solved, and the positive and negative temperature coefficient voltages are improved by adjusting the proportion of the band gap reference self resistors at different temperatures. According to the compensation method provided by the embodiment of the application, no additional design of current or voltage of a high-order temperature coefficient is needed, no summation circuit is needed for superposition, sliding temperature compensation is finally realized by changing the weighted superposition proportion of the positive and negative temperature coefficients in the band gap, any band gap reference structure for realizing the voltage superposition of the positive and negative temperature coefficients by means of the resistance proportion can be met, and the universality is strong.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute an undue limitation to the application. In the drawings:
FIG. 1 is a schematic diagram of an alternative positive temperature coefficient voltage generation in an embodiment of the present application;
FIG. 2 is an alternative schematic diagram of a Brokaw bandgap reference in accordance with an embodiment of the present application;
FIG. 3 is a schematic diagram of an alternative bandgap reference slip temperature compensation circuit according to an embodiment of the present application;
FIG. 4 is a flow chart of an alternative bandgap reference slip temperature compensation method of an embodiment of the present application;
FIG. 5 is an alternative slip compensated bandgap reference schematic diagram of an embodiment of the present application, exemplified by a Brokaw type bandgap reference structure;
FIG. 6 is a schematic diagram of a slip compensated bandgap reference of yet another alternative bandgap reference structure in accordance with embodiments of the present application;
FIG. 7 is a schematic simulation diagram of compensation results without trimming bits according to an alternative embodiment of the present application;
FIG. 8 is a schematic simulation diagram of compensation results when 1 trim bit is optionally set according to an embodiment of the present application;
FIG. 9 is a schematic simulation diagram of compensation results when 2 trim bits are optionally set according to an embodiment of the present application;
FIG. 10 is a schematic simulation diagram of compensation results when 3 trim bits are optionally set according to an embodiment of the present application;
FIG. 11 is a graph showing the comparison between the compensation results at different trimming bits.
Detailed Description
The present application will be described in detail hereinafter with reference to the accompanying drawings in conjunction with embodiments. It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other.
It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.
The basic principle of the band gap reference is to use the voltage of positive and negative temperature coefficients generated by the triode to carry out superposition to generate the reference voltage of zero temperature coefficient. Base-emitter voltage of bipolar transistor
Has a negative temperature coefficient. Collector current of bipolar transistor>
And saturation current->
The relation between the two is:
. Wherein->
Is base emitter voltage, also negative temperature coefficient voltage, +.>
Is temperature voltage equivalent, also positive temperature coefficient voltage, ">
。
Proportional to absolute temperature, < >>
The change with temperature can be represented by the following formula:
。
FIG. 1 is a schematic diagram of an alternative positive temperature coefficient voltage generation in an embodiment of the present application. As shown in fig. 1, transistor Q 1 Is connected with a current source
Transistor Q 2 Is connected with a current sourceI 0 When two bipolar transistors Q 1 And Q 2 Operating at unequal currents +.>
The difference between them is proportional to absolute temperature and the specific relationship is expressed by the following formula:
Wherein->
Is Q 1 And Q 2 The ratio of the two branch currents.
The two temperature coefficient voltages are weighted and overlapped through a certain circuit structure, so that the voltage irrelevant to the approximate temperature can be obtained. Fig. 2 is an alternative Brokaw bandgap reference schematic diagram in accordance with an embodiment of the present application. As shown in fig. 2, the MOS transistor M 1 Gate and of (2)MOS tube M 2 Is connected with the grid electrode of M 1 Is connected to the drain of transistor Q 1 Collector, M of 2 Is connected to the drain of transistor Q 2 Collector, Q of 1 Base and Q of (2) 2 Is connected with the base electrode of Q 2 Emitter connection resistor R of (2) 2 The reference voltage value obtained by weighted superposition is:
wherein,,V T is a voltage with a positive temperature coefficient (positive temperature coefficient),V be is a negative temperature coefficient voltage which itself varies with temperature and is a positive temperature coefficient voltageV T Not change with temperature (V T The positive temperature coefficient KT/q of (c) is a fixed value), so that even if the weights are precisely matched, the approximate temperature coefficient independent voltage obtained by weighted superposition can still change slightly with temperature. At the same time receive triode Q 1 And Q 2 A kind of electronic device
The finite value affects the base current of some transistors, which can cause the mismatch of the left and right current paths and also affect the temperature coefficient.
The temperature coefficient achieved by a fixed weighted overlap ratio is limited due to non-idealities. The temperature coefficient of the band gap can be improved by adopting different weighted superposition ratios under different temperature conditions. The temperature profile of the final band gap is the envelope of the band gap reference temperature profile with different n clusters of proportionality coefficients. Wherein each cluster curve can be expressed as:
wherein T is n For the nth cluster of temperature profiles,kis a weighted proportion. The band gap reference generates positive temperature coefficient current in the generation process of the reference voltage, and the current changes by more than 100% within the range of-40-125 ℃, so that the positive temperature coefficient current changes with temperatureThe change characteristics of (a) can be used as a judgment condition for the adjustment of the scaling factor.
Fig. 3 is a schematic diagram of an alternative bandgap reference slip temperature compensation circuit, as shown in fig. 3, including a bandgap reference circuit and a trimming circuit, according to embodiments of the application, wherein,V REF for the output reference voltage, the trimming circuit is configured to: comparing the magnitude relation of n positive temperature coefficient currents and n zero temperature coefficient currents of the band gap reference circuit, and controlling the proportion of controllable resistors in the band gap reference circuit according to the comparison result, wherein n is an integer greater than 0.
It should be noted that the ratio of the controllable resistors in the bandgap reference circuit may be understood that each group of controllable resistors in the bandgap reference circuit may be controlled by switching on and off a switch to control the short circuit or conduction of the resistors, and the size of the controllable resistors in the bandgap reference circuit may be adjusted by adjusting the ratio of the number of controllable resistors connected in series. The resistance values of m groups of controllable resistors can be the same or different, and the embodiment of the application is not limited to this.
In one embodiment, the trimming circuit may include:
a zero temperature coefficient current array (IREF) comprising n zero temperature coefficient currents in one-to-one correspondence with n positive temperature coefficient currents (IPTAT) of the bandgap reference circuit;
the current comparator array comprises n current comparators and is configured to compare the magnitude relation between positive temperature coefficient current and zero temperature coefficient current of the band gap reference circuit corresponding to each path;
the switch array comprises m groups of switches, m groups of controllable resistors connected with the band gap reference circuit are respectively controlled, and the switch array is configured to control on-off of the m groups of controllable resistors according to the comparison result output by the current comparator array, wherein m is an integer greater than 0.
In one embodiment, the trimming circuit further comprises: and the decoder is respectively connected with the current comparator array and the switch array, and is configured to convert the thermometer code output by the current comparator array into a binary code and control the on and off of the switch array.
The decoder may be a thermometer code-binary code decoder, and may convert the thermometer code output from the current comparator array into a binary code.
By adding a current comparator array, a decoder and a switch array on the basis of the traditional band gap reference and adjusting different controllable resistance feedback coefficients under different temperature conditions, temperature compensation in a wide temperature range can be realized. The specific scheme is as follows:
a current reference array comprising n sets of zero temperature coefficient currents is provided and compared to the positive temperature coefficient currents in the bandgap by n sets of current comparators. During the temperature rise, the outputs of the n groups of current comparators change in thermometer code. And then inputting the value of the thermometer code into a thermometer code-binary code decoder, and controlling a switch array to change the weighted superposition proportion of positive and negative temperature coefficients in the band gap after decoding, so as to finally realize sliding temperature compensation. It should be noted that the decoding rule of the decoder is not limited to the conversion from thermometer code to binary code, and can be set arbitrarily according to the temperature drift condition.
Taking binary decoding as an example, n and m satisfy
. Taking m=3 and n=7 as an example, when the output of the n-path current comparator array is 0000000, m=111, and all three switches are closed; when the output of the n-path current comparator array is 0000001, m=110, the switch 2 and the switch 3 are closed, and the switch 1 is opened; when the output of the … … n-path current comparator array is 0111111, m=001, the switch 2 and the switch 3 are opened, and the switch 1 is closed; when the n-way current comparator array output is 1111111, m=000, and all three switches are turned off.
When the comparator array outputs are all 0, i.e. positive temperature coefficient current
To->
Are all smaller than zero temperature coefficientWhen the current is, the decoder output is all 1, the switch array is +.>
All-on->
The controllable resistors are all short-circuited, and R is connected at the moment 2 The total resistance of the resistors of the branch circuit is the smallest. When the comparator array outputs all 1's, i.e. positive temperature coefficient current +.>
To the point of
When the current is larger than zero temperature coefficient current, the output of the decoder is 0, and the switch array is +.>
The full-closed state is realized,
the controllable resistors are all conducted, and R is connected at the moment 2 The total resistance of the resistors of the branch circuit is the largest.
Adjusting the combination of the conduction of the switch array, R 2 The resistance of the branch circuit can change, and the output reference voltage is shown in the following formula:
V be is of negative temperature coefficient voltage, V T For positive temperature coefficient voltage, R is adjusted 2 The weighted overlap ratio of the positive and negative temperature coefficients is adjusted.
FIG. 4 is a flow chart of an alternative bandgap reference slip temperature compensation method according to an embodiment of the present application. As shown in fig. 4, in one embodiment of the present application, a bandgap reference sliding temperature compensation method is also provided, including:
s1, comparing the magnitude relation of n paths of positive temperature coefficient currents and n paths of zero temperature coefficient currents of a band gap reference circuit to obtain a comparison result of each path, wherein the n paths of zero temperature coefficient currents are in one-to-one correspondence with the n paths of positive temperature coefficient currents of the band gap reference circuit, and n is an integer larger than 0;
s2, controlling the proportion of the controllable resistor in the band-gap reference circuit according to the comparison result.
In an embodiment, step S1 may be implemented by:
s11, each group is provided with
And->
Respectively connected to two ends of the nth current comparator, outputting thermometer codes through the current comparator array, wherein +_>
To->
For n equal positive temperature coefficient currents in the bandgap reference circuit +.>
For zero temperature coefficient current, each path of current satisfies +.>
；
S12, controlling the switch array through the value of the thermometer code
Wherein the switch array is +.>
For controlling m groups of controllable resistances +.>
Is provided.
In an embodiment, the step S12 may be implemented by:
s121, when
Is greater than->
When the nth bit output of the current comparator array is 1;
s122, converting thermometer codes output by the current comparator array into binary signaling through a decoder;
s123, controlling the switch array through the binary signaling
Is turned on and off, wherein,
。
fig. 5 is a schematic diagram of an alternative slip compensated bandgap reference, for example a Brokaw bandgap reference structure, in accordance with an embodiment of the present application. As shown in fig. 5, the bandgap reference circuit includes: first MOS tube M 1 Second MOS tube M 2 First transistor Q 1 、n q Second transistors Q connected in parallel 2 A first resistor R 1 A second resistor R 2 And m groups of controllable resistors
Wherein, the first MOS tube M 1 The source electrode of the transistor is connected with a power supply, and the grid electrode of the transistor is connected with a second MOS tube M 2 A drain connected to the gate and the drain of the first transistor Q 1 Collector electrode of the second MOS transistor M 2 The source electrode is connected with a power supply, the drain electrode is connected with a second transistor Q 2 Collector of the second transistor Q 2 The emitter of (a) is connected with the first resistor R 1 Is a first resistor R 1 And the other end of the first transistor Q 1 The emitters of the (C) are connected with the second resistor R 2 M groups of controllable resistors->
And the second resistor R 2 Serial connection; the trimming circuit comprises: third MOS transistor array M 3-1 -M 3-n Zero temperature coefficient current array->
Current comparator array, decoder, switch array +.>
Wherein the third MOS transistor array M 3-1 -M 3-n The source electrodes of the second MOS tube M are connected with a power supply, and the grid electrodes of the second MOS tube M are connected with the second MOS tube M 2 The drain electrodes are respectively connected with the current comparator array, and the third MOS transistor array M 3-1 -M 3-n For generating n-way positive temperature coefficient current, zero temperature coefficient current array->
The current comparator array is connected with the decoder, and the decoder is connected with the switch array +.>
Switch array->
Respectively control and connect m groups of controllable resistors +.>
。
Take Brokaw bandgap reference structure as an example, wherein
N equal positive temperature coefficient currents (IPTAT).
For zero temperature coefficient current, each path of current satisfies +.>
. Every group->
And->
The output of the current comparator is connected with the decoder, and the output result is encoded in the form of thermometer codes. When->
Greater than
When the nth bit output is 1, i.e., the higher the temperature, the more bits the current comparator array outputs 1. The decoder converts the thermometer code into a binary code and controls the switch array +.>
Is turned on and off.
For m groups of controllable resistors, the resistance values satisfy:
。
The larger the m value is, the finer the scaling factor is adjusted, and the smaller the temperature coefficient of the compensated reference is.
Fig. 6 is a schematic diagram of a slip compensated bandgap reference of yet another alternative bandgap reference structure in accordance with an embodiment of the present application. As shown in fig. 6, in one embodiment, the bandgap reference circuit includes: amplifier OPAMP, fourth MOS tube M 4 Fifth MOS tube M 5 Sixth MOS transistor M 6 Third transistor Q 3 、n q Fourth transistors Q connected in parallel 4 Fifth transistor Q 5 Third resistor R 3 Fourth resistor R 4 And m groups of controllable resistors
Wherein the fourth MOS tube M 4 The fifth MOS tube M 5 The sixth MOS tube M 6 The sources of the fourth MOS tube M are all connected with a power supply 4 The fifth MOS tube M 5 The sixth MOS tube M 6 The grid electrodes of the amplifier OPAMP are connected with each other, the output end of the amplifier OPAMP is connected with the fourth MOS tube M 4 A gate electrode with a negative input terminal connected toIs connected with the third transistor Q 3 Emitter and fourth MOS transistor M 4 The positive input end of the third resistor R is connected with the drain electrode of the third resistor R in turn 3 One end and a fifth MOS tube M 5 The third resistor R 3 Is connected to the fourth transistor Q 4 An emitter of the sixth MOS transistor M 6 The drain electrodes of the fourth resistor R are connected in turn 4 And the fifth transistor Q 5 The fourth resistor R 4 And the fifth transistor Q 5 The m groups of controllable resistors are connected in series>
The bases and the collectors of the third transistor, the fourth transistor and the fifth transistor are grounded; the trimming circuit comprises: seventh MOS transistor array M 7-1 -M 7-n Zero temperature coefficient current array->
Current comparator array, decoder, switch array +.>
Wherein the seventh MOS transistor array M 7-1 -M 7-n The source electrodes of the MOS transistors are connected with a power supply, and the grid electrodes of the MOS transistors are connected with the sixth MOS transistor M 6 The drain electrodes of the MOS transistor array M are respectively connected with the current comparator array, and the seventh MOS transistor array M 7-1 -M 7-n For generating the n paths of positive temperature coefficient current, the zero temperature coefficient current array
The current comparator array is connected with the decoder, and the decoder is connected with the switch array>
Said switch array->
Respectively controlling and connecting the m groups of controllable resistors +.>
。
The bandgap reference operates in a manner similar to the Brokaw type of reference described above, and also produces a voltage with approximately zero temperature coefficient by superposition of positive and negative temperature coefficient voltages. The output voltage can be expressed as:
。
the compensation scheme provided by the embodiment of the application can be directly applied to the band gap reference. By varying at different temperatures
The resistance of the branch circuit changes the superposition proportion of positive temperature coefficients, thereby realizing the compensation of temperature drift.
Fig. 7 to 10 show the compensation result diagrams when m is taken from 0 to 3, respectively. Fig. 7 to 10 are compensation results of no trimming bit, 1 trimming bit, 2 trimming bits, 3 trimming bits, respectively. FIG. 11 is a comparison result between different trimming bits. Wherein, a trimming bit corresponds to a current comparator and a switch. It can be seen that the process applied in the examples of the present application, under no trimming, had a difference between the maximum and minimum output values of the reference voltage in the range of-40 ℃ to 85 ℃ of 18.51mV; the difference after applying 1 trimming bit is 16.3mV; the difference after applying 2 trimming bits is 11.11mV; the difference after applying 3 trimming bits is 6.91mV. It can be intuitively seen from fig. 11 that after a plurality of trimming bits are applied, the temperature drift of the reference voltage is significantly improved, and the larger the value of m is, the better the compensation result is.
It is to be understood that the invention is not limited in its application to the examples described above, but is capable of modification and variation in light of the above teachings by those skilled in the art, and that all such modifications and variations are intended to be included within the scope of the appended claims.
The idea proposed in the embodiment of the present application is different from the compensation scheme of the conventional bandgap reference. The traditional scheme is to additionally construct a path of current or voltage with a high-order temperature coefficient to be overlapped with the band gap reference so as to realize temperature compensation. The compensation scheme in the embodiment of the application is to adjust the proportion of the self-controllable resistor of the band gap reference at different temperatures to improve the positive and negative temperature coefficient voltages and thereby improve the temperature coefficient. No additional design of the current or voltage of the higher order temperature coefficient is required, nor is the summation circuit designed to perform superposition. In addition, the scheme can meet any band gap reference structure which realizes the superposition of positive and negative temperature coefficient voltages by means of resistance proportion, and has strong universality.
The foregoing embodiment numbers of the present application are merely for describing, and do not represent advantages or disadvantages of the embodiments.
In the foregoing embodiments of the present application, the descriptions of the embodiments are emphasized, and for a portion of this disclosure that is not described in detail in this embodiment, reference is made to the related descriptions of other embodiments.
The foregoing is merely a preferred embodiment of the present application and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present application and are intended to be comprehended within the scope of the present application.
Claims (8)
1. The band gap reference sliding temperature compensation circuit is characterized by comprising a band gap reference circuit and a trimming circuit, wherein the band gap reference circuit comprises a controllable resistor, and the trimming circuit comprises: the zero temperature coefficient current array comprises n paths of zero temperature coefficient currents, and the zero temperature coefficient current array corresponds to n paths of positive temperature coefficient currents of the band gap reference circuit one by one, wherein n is an integer greater than 0; the current comparator array comprises n current comparators and is configured to compare the magnitude relation between the positive temperature coefficient current and the zero temperature coefficient current of the band gap reference circuit corresponding to each path; the switch array comprises m switches, m groups of controllable resistors connected with the band gap reference circuit are respectively controlled, and the switch array is configured to control the on-off of the m groups of controllable resistors according to the comparison result output by the current comparator array, wherein m is an integer greater than 0; the trimming circuit is configured to: comparing the magnitude relation between the n paths of positive temperature coefficient currents of the band-gap reference circuit and the n paths of zero temperature coefficient currents externally connected, and controlling the proportion of controllable resistors in the band-gap reference circuit according to the comparison result.
2. The bandgap reference slip temperature compensation circuit of claim 1, wherein said trimming circuit further comprises:
and the decoder is respectively connected with the current comparator array and the switch array, and is configured to convert the thermometer code output by the current comparator array into a binary code and control the on and off of the switch array.
3. The bandgap reference slip temperature compensation circuit of claim 2, wherein,
the bandgap reference circuit includes: first MOS tube (M) 1 ) Second MOS transistor (M) 2 ) A first transistor (Q 1 ）、n q Second transistors (Q) 2 ) A first resistor (R 1 ) A second resistor (R 2 ) And m groups of controllable resistors
-
) Wherein the first MOS transistor (M 1 ) The source electrode of the second MOS tube is connected with a power supply, and the grid electrode of the second MOS tube is connected with the second MOS tube (M 2 ) And a drain connected to the gate and drain of the first transistor (Q 1 ) Is arranged in the second MOS tube (M 2 ) Is connected to a power source, and a drain is connected to the second transistor (Q 2 ) Is connected to the collector of the second transistor (Q 2 ) Is connected with the first resistor (R 1 ) Is arranged at one end of the first resistor (R 1 ) And the other end of the first transistor (Q 1 ) Is connected to the emitter of the second resistor (R 2 ) The m groups of controllable resistors (+)>
-
) And the second resistor (R 2 ) Serial connection;
the trimming circuit comprises: third MOS transistor array (M) 3-1 -M 3-n ) Zero temperature coefficient current array
-
) Current comparator array, decoder, switch array (+)>
-
) Wherein the third MOS transistor array (M 3-1 -M 3-n ) The source electrodes of the second MOS tube are connected with a power supply, and the grid electrodes of the second MOS tube are connected with a second MOS tube (M 2 ) The drain electrodes are respectively connected with the current comparator array, the third MOS transistor array (M 3-1 -M 3-n ) For generating said n-way positive temperature coefficient current, said zero temperature coefficient current array (>
-
) The current comparator array is connected with the decoder, and the decoder is connected with the switch array (/ -)>
-
) Said switch array (>
-
) Respectively controlling and connecting the m groups of controllable resistors (& lt, & gt)>
-
）。
4. The bandgap reference slip temperature compensation circuit of claim 2, wherein,
the bandgap reference circuit includes: amplifier OPAMP, fourth MOS transistor (M) 4 ) Fifth MOS transistor (M) 5 ) Sixth MOS transistor (M) 6 ) Third transistor (Q) 3 ）、n q Fourth transistors (Q) 4 ) Fifth transistor (Q) 5 ) A third resistor (R 3 ) Fourth resistor (R) 4 ) And m groups of controllable resistors
-
) Wherein the fourth MOS transistor (M 4 ) The fifth MOS tube (M) 5 ) The sixth MOS transistor (M) 6 ) The sources of the fourth MOS tube (M) 4 ) The fifth MOS tube (M) 5 ) The sixth MOS transistor (M) 6 ) The grid electrodes of the amplifier OPAMP are connected with each other, the output end of the amplifier OPAMP is connected with the fourth MOS tube (M 4 ) A negative input terminal connected to the gate of the third transistor (Q 3 ) Emitter and fourth MOS transistor (M) 4 ) The positive input end of the third resistor (R 3 ) One end and a fifth MOS tube (M) 5 ) Is connected to the drain electrode of the third resistor (R 3 ) Is connected with the other end of the fourthTransistor (Q) 4 ) The emitter of the sixth MOS transistor (M 6 ) Is connected in turn to the drain of the fourth resistor (R 4 ) And the fifth transistor (Q 5 ) The fourth resistor (R 4 ) And the fifth transistor (Q 5 ) The m groups of controllable resistors are connected in series between the two>
-
) Third transistor (Q 3 ) Fourth transistor (Q) 4 ) And a fifth transistor (Q 5 ) Both the base and the collector of (2) are grounded;
the trimming circuit comprises: seventh MOS transistor array (M) 7-1 -M 7-n ) Zero temperature coefficient current array
-
) Current comparator array, decoder, switch array (+)>
-
) Wherein the seventh MOS transistor array (M 7-1 -M 7-n ) The source electrodes of the MOS transistors are connected with a power supply, and the grid electrodes of the MOS transistors are connected with the sixth MOS transistor (M 6 ) The drain electrodes are respectively connected with the current comparator array, and the seventh MOS transistor array (M 7-1 -M 7-n ) For generating said n-way positive temperature coefficient current, said zero temperature coefficient current array (>
-
) The current comparator array is connected with the decoder, and the decoder is connected with the switch array (/ -)>
-
) Said switch array (>
-
) Respectively controlling and connecting the m groups of controllable resistors (& lt, & gt)>
-
）。
5. The bandgap reference slip temperature compensation circuit of claim 1, wherein said n-way positive temperature coefficient current
To->
The magnitudes of the n zero temperature coefficient currents satisfy the following formula:
。
6. a bandgap reference slip temperature compensation method, comprising:
comparing the magnitude relation of n paths of positive temperature coefficient currents and n paths of zero temperature coefficient currents of a band gap reference circuit to obtain a comparison result of each path, wherein the n paths of zero temperature coefficient currents are in one-to-one correspondence with the n paths of positive temperature coefficient currents of the band gap reference circuit, and n is an integer larger than 0;
and controlling the proportion of controllable resistance in the band gap reference circuit according to the comparison result.
7. The method of claim 6, wherein comparing the magnitude relation between n positive temperature coefficient currents and n zero temperature coefficient currents of the bandgap reference circuit to obtain the comparison result of each path comprises:
each group is provided with
And->
Respectively connected to two ends of the nth current comparator, outputting thermometer codes through the current comparator array, wherein +_>
For n equal positive temperature coefficient currents in the bandgap reference circuit +.>
For zero temperature coefficient current, each path of current satisfies +.>
；
Control switch array according to the value of the thermometer code
-
Wherein the switch array is turned on and off
-
For controlling m groups of controllable resistances +.>
-
Is provided.
8. The bandgap reference slip temperature compensation method of claim 7, wherein said controlling of said switch array is based on values of said thermometer codes
-
Is turned on and off, comprising:
when (when)
Is greater than->
When the nth bit output of the current comparator array is 1; />
Converting thermometer codes output by the current comparator array into binary signaling through a decoder;
controlling the switch array by the binary signaling
-
Is turned on and off, wherein->
。/>
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310043501.7A CN115793769B (en) | 2023-01-29 | 2023-01-29 | Band gap reference sliding temperature compensation circuit and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310043501.7A CN115793769B (en) | 2023-01-29 | 2023-01-29 | Band gap reference sliding temperature compensation circuit and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115793769A CN115793769A (en) | 2023-03-14 |
| CN115793769B true CN115793769B (en) | 2023-06-02 |
Family
ID=85429019
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310043501.7A Active CN115793769B (en) | 2023-01-29 | 2023-01-29 | Band gap reference sliding temperature compensation circuit and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115793769B (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104298294B (en) * | 2013-07-19 | 2016-02-24 | 中国科学院上海微系统与信息技术研究所 | With the source compensated by using high-order curvature reference voltage source trimmed |
| CN111448531B (en) * | 2017-12-05 | 2022-09-09 | 赛灵思公司 | Programmable temperature coefficient analog second-order curvature compensation voltage reference and fine tuning technique of voltage reference circuit |
| CN212723774U (en) * | 2020-08-17 | 2021-03-16 | 深圳天狼芯半导体有限公司 | Reference voltage generating circuit, voltage stabilizing circuit and chip |
| CN112000170B (en) * | 2020-09-02 | 2022-03-11 | 恒烁半导体(合肥)股份有限公司 | NOR Flash analog multiplier and application thereof |
| CN112667015A (en) * | 2020-12-01 | 2021-04-16 | 江苏信息职业技术学院 | Current trimming circuit for band-gap reference |
-
2023
- 2023-01-29 CN CN202310043501.7A patent/CN115793769B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN115793769A (en) | 2023-03-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102270008B (en) | Band-gap reference voltage source with wide input belt point curvature compensation | |
| US5764174A (en) | Switch architecture for R/2R digital to analog converters | |
| CN112558675B (en) | Bandgap reference voltage generating circuit | |
| CN111835305A (en) | Novel programmable linear equalization circuit | |
| CN113721694B (en) | Self-compensating band gap reference source structure based on curvature function and application thereof | |
| CN102253684A (en) | Bandgap reference circuit employing current subtraction technology | |
| CN114527823A (en) | Low-temperature drift high-precision band-gap reference voltage source with current trimming function | |
| CN107425845B (en) | Superposition operation circuit and floating voltage digital-to-analog conversion circuit | |
| CN115412092A (en) | High-linearity tailless current-steering digital-to-analog converter | |
| CN115793769B (en) | Band gap reference sliding temperature compensation circuit and method | |
| CN111817719B (en) | Reference level buffer suitable for pipelined ADC and pipelined ADC | |
| CN115857608B (en) | Band-gap reference source for realizing high-order temperature compensation in wide range by using depletion tube | |
| JP3408788B2 (en) | I / V conversion circuit and DA converter | |
| CN110879626A (en) | Reference circuit under low power supply voltage | |
| CN115857601A (en) | High-performance band-gap reference circuit | |
| US6906588B2 (en) | Variable-gain differential input and output amplifier | |
| CN211123820U (en) | Reference circuit under low power supply voltage | |
| CN108319323B (en) | CMOS high-temperature reference voltage source | |
| CN202075651U (en) | High-order curvature compensation band-gap resistance voltage source | |
| CN108227814B (en) | Source follower circuit | |
| CN117519403B (en) | Band gap reference circuit and electronic equipment | |
| CN111064453A (en) | Voltage comparator | |
| CN108988861B (en) | Current mode margin amplifier | |
| CN115220519B (en) | Temperature compensation circuit and method based on Zener diode | |
| CN116805859B (en) | Operational amplifier offset voltage regulation circuit and method |
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 |