CN1350368A

CN1350368A - Correction System of Component Errors in Integrated Circuit Manufacturing Process

Info

Publication number: CN1350368A
Application number: CN 00131937
Authority: CN
Inventors: 刘宇华
Original assignee: BenQ Corp
Current assignee: BenQ Corp
Priority date: 2000-10-25
Filing date: 2000-10-25
Publication date: 2002-05-22
Anticipated expiration: 2020-10-25
Also published as: CN1194468C

Abstract

A component error correcting system for correcting the component error of IC caused by manufacture technology is composed of a current source for outputting two currents in a certain proportion, a voltage divider circuit formed on IC and having at least one output terminal for receiving one current from current source and outputting a divided voltage, a reference voltage generator for receiving another current from current source and outputting a reference voltage, a comparator circuit connected to output terminal of voltage divider circuit for receiving the divided voltage and comparing it with reference voltage to generate relative comparison signal, and a correcting circuit connected to comparator circuit for correcting the component error of IC based on the comparison signal.

Description

The update the system of component error in the integrated circuit fabrication process

The invention provides a kind of component error update the system, refer to a kind of update the system that is used for the resistance error that the modifying factor integrated circuit fabrication process causes especially.

In today in the flourishing epoch of science and technology, each aspect that integrated circuit has extensively been applied to live is little of electronic watch and mobile phone, big to powerful super computer, the trace of invisible integrated circuit nowhere.Yet because of the problem of manufacturing process control aspect, the characteristic of each element in the integrated circuit may depart from the characteristic of original design, makes the overall performance of this integrated circuit not as the ideal of original design.As the resistive element in the integrated circuit, just may be because of the not desirable to the greatest extent error that produces in the part manufacturing process.So the manufacturing process deviation can make the actual resistance of all resistive elements in this integrated circuit all depart from former design load with identical ratio, that is to say, to depart from the ratio of former design load all identical for the resistance value of each resistive element on this integrated circuit.

At above-mentioned resistance error, U.S. Pat 5,625,316 once proposed an error correction systems, were used for revising the resistance error in the filter circuit.Please refer to Fig. 1, Fig. 1 is existing component error update the system 510, is used for revising the circuit block diagram of filter circuit 520 resistance errors.Filter circuit 520 comprises a resistance R _ f and a variable capacitance 560, this both product, and just so-called RC time constant has determined the frequency range of filter circuit 520; If the resistance of resistance R _ f is influenced by integrated circuit fabrication process and error is arranged, just may make the frequency range of filter circuit 520 depart from former design load.In order to keep frequency range certain, component error update the system 510 changes the error of the capacitance of variable capacitance 560 with compensation Rf.

In existing component error update the system 510, Vcc provides the bias voltage of update the system 510, resistive element Rref one is arranged at the outer meeting resistance of integrated circuit outside, its resistance value is not subjected to the influence of this integrated circuit fabrication process, resistance R c then with filter circuit 520 in resistance R _ f manufacture in same integrated circuit fabrication process, so both have identical resistance relative error.Update the system 510 comprises a voltage stabilizing in addition and produces circuit 530, is used for producing a normal voltage Vbg, and a reference voltage generator 540 is used for producing a reference voltage Vref by normal voltage Vbg, and an analog/digital converter 550.

The operation principle of existing component error update the system 510 is as follows: voltage stabilizing produces circuit 530 and produces normal voltage Vbg, normal voltage Vbg is input reference voltage generator 540 and be converted to reference voltage Vref on the one hand, be buffered to the end of outer meeting resistance Rref on the other hand via operational amplifier P, setting up a reference current Iref by the cross-pressure (Vcc-Vbg) of Rref (is Iref=(Vcc-Vbg)/Rref), reference current Iref can flow into via transistor T and produce comparative voltage Vc among the resistance R c, as previously mentioned, resistance R _ f in resistance R c and the filter circuit 520 has the resistance error of same ratio, size by comparison reference voltage Vref and comparative voltage Vc, can understand the resistance error of the resistance R _ f in resistance R c and the filter circuit 520, and analog/digital converter 550 is exactly to be used for comparison reference voltage Vref and comparative voltage Vc and produce the capacitance that corresponding control signal changes variable capacitance 560 in the filter circuit 520, so that resistance error is done compensation.

The shortcoming of component error update the system 510 is that it must utilize Vcc and Vbg could set up normalized current Iref.In some electronic installation, especially in portable electron device, its inner integrated circuit is by electric storage device power supplies such as batteries, and along with the consumption of power supply, the bias voltage Vcc that this electric storage device provided also can misalignment.Under the situation of bias voltage Vcc misalignment, even producing circuit 530, voltage stabilizing can provide stable voltage Vbg, also can't correctly set up normalized current Iref.Thus, the reference current Iref of mistake and resistance R c just can produce wrong comparative voltage Vc, and the comparative voltage Vc with mistake compares with correct reference voltage Vref when analog/digital converter 550, and nature can't correctly be revised resistance error.

Therefore, main purpose of the present invention is to provide a kind of component error update the system, use current generator to come to provide electric current to outer meeting resistance and series resistance respectively, make outer meeting resistance and series resistance the reference voltage and the dividing potential drop of ratio such as be produced, revise resistance error mistakenly because of the fluctuations of power supply to avoid the component error update the system.

For reaching above-mentioned purpose, a scheme of the present invention provides a kind of component error update the system, includes: a reference voltage generator, include an outer meeting resistance, and be electrically connected on an integrated circuit; One bleeder circuit, it includes at least one series resistance, is formed on this integrated circuit; One current generator, be electrically connected on this reference voltage generator and this bleeder circuit, be used for respectively to this outer meeting resistance and this series resistance supply of current, so that this reference voltage generator is able to produce a reference voltage and make this bleeder circuit be able to produce a dividing potential drop in its output in its output; And a comparison circuit, be electrically connected on the output of this bleeder circuit, whether be used for the size of dividing potential drop that relatively this bleeder circuit produced and this reference voltage has error with the resistance value of the series resistance of monitoring this bleeder circuit.

Another program of the present invention provides a kind of update the system that is used for adjusting RC filter frequency range, and this RC filter comprises a resistance and a capacitor array, and this update the system includes: an outer meeting resistance comprises a reference voltage end; One bleeder circuit comprises one fen pressure side; One current generator is supplied the electric current of equal proportion to this outer meeting resistance and this bleeder circuit respectively, so that the reference voltage end of this outer meeting resistance produces a reference voltage and make the branch pressure side of this bleeder circuit produce a dividing potential drop; One A/D conversion circuit is used for the relatively size of this dividing potential drop and this reference voltage, and exports a digital signal and produce different capacitances to control this capacitor array.

Another scheme of the present invention provides a kind of update the system of adjusting IC interior RC filter, this RC filter comprises a resistance and a capacitor array, this update the system includes: an outer meeting resistance, be arranged at this integrated circuit outside, and comprise a reference voltage end; One bleeder circuit is arranged at this IC interior, is made up of at least one series resistance, comprises one fen pressure side; One current generator is supplied the electric current of equal proportion to this outer meeting resistance and this bleeder circuit respectively, so that the reference voltage end of this outer meeting resistance produces a reference voltage and make the branch pressure side of this bleeder circuit produce a dividing potential drop; One A/D conversion circuit is used for the relatively size of this dividing potential drop and this reference voltage, and exports different digital signals according to the variation of this series resistance and produce different capacitances to control this capacitor array.

Description of drawings:

Fig. 1 is used for revising the circuit block diagram of filter circuit resistance error for existing component error update the system.

Fig. 2 applies to the schematic diagram of filter circuit for component error update the system of the present invention.

Fig. 3 applies to the circuit diagram of filter circuit for Fig. 2 component error update the system.

Fig. 4 is each node of Fig. 3 bleeder circuit the resistance value of extremely holding and the function relation figure of resistance relative error.

Fig. 5 changes the schematic diagram of opening or closing for each correction circuit unit of Fig. 3 with the resistance relative error.

Please refer to Fig. 2, Fig. 2 applies to the schematic diagram of a RC filter circuit 70 for component error update the system 10 of the present invention.Component error update the system 10 comprises a current generator 20, and current generator 20 can produce two electric currents, exports a reference voltage generator 30 and a bleeder circuit 40 respectively to.The reference voltage that the dividing potential drop of bleeder circuit 40 and reference voltage generator 30 are produced is then imported two inputs of a comparison circuit 50 respectively, its result relatively then imports a correction circuit 60, comes filter circuit 70 is carried out necessary correction with control correction circuit 60.In the present embodiment, correction circuit 60 is to be equivalent to a variable capacitance, and it is to be electrically connected on filter circuit 70 with parallel way.Comparison circuit 50 then is as an A/D conversion circuit, is used for converting the output signal of bleeder circuit to suitable digital signal with control correction circuit 60.As shown in Figure 2, filter circuit 70 comprises an operational amplifier Q, its main filter element is made up of a resistance R _ f and a capacitor C f, if the resistance value of resistance R _ f is former design load because of manufacturing process departs from, can relatedly influence the resistance value of resistance R _ f and the product of capacitor C f and correction circuit 60 interior variable capacitance total capacitance values.In other words, the error of integrated circuit fabrication process can change the RC time constant of filter circuit 70, makes the frequency range of filter circuit 70 produce error, can't operate as normal.Therefore the capacitance of the variable capacitance in the correction circuit 60 must change along with the error of resistance R _ f, departs from former design load along with resistance error with the filter frequency range of avoiding filter circuit 70 and correction circuit 60 to be determined.

Please refer to Fig. 3.Fig. 3 is used for the circuit diagram of filter circuit 70 for component error update the system 10.Current generator 20 is a current mirror, and it comprises two transistor MPA 11 and MPA 14, and both all provide Dc bias by Vcc and VG1.With semi-conductive manufacturing process technology, transistor MPA 11 and MPA 14 both areas can be held in M than the scale dimension of (spect ratio, i.e. W/L ratio): N, it is M: N that the electric current that both are produced respectively in the preset working district is also kept ratio.Reference voltage generator 30 comprises an outer meeting resistance Rref, and outer meeting resistance Rref is located at outside this integrated circuit, and is electrically connected on the ground end of transistor MPA 14 and this integrated circuit in the current generator 20 respectively.Because outer meeting resistance Rref is located at outside this integrated circuit, its resistance value is not subjected to the influence of this integrated circuit fabrication process error, and the relative error of its resistance value can be maintained at one thousandth to one of percentage usually, so outer meeting resistance Rref can be as an error standard of comparison.Across the voltage of outer meeting resistance Rref, then be a reference voltage Vref.

The bleeder circuit 40 of component error update the system 10 of the present invention is to be made of a plurality of divider resistances.Please refer to Fig. 3.These divider resistances comprise R2, R3, R4, R5, R6, R7 and R8; The node that each divider resistance electric current flows into end then is labeled as L15, L10, L05, T1, H05, H10 and H15 respectively.Divider resistance and the resistance R _ f in the filter circuit 70 by R2 to R8 are built on the same integrated circuit, each resistance is all finished in same manufacturing process, so R2 to R8 each divider resistance has identical resistance relative error with resistance R _ f in the filter circuit 70, in other words, for each resistance, between actual resistance and the original design value fixing ratio should be arranged.

As shown in Figure 3, the comparison circuit 50 of component error update the system 10 comprises six comparators.These six comparators respectively have two inputs and an output.These comparators can compare the size of two input terminal voltages, and by this output output result relatively.And six comparators in comparison circuit 50, its first input end is electrically connected on six node H15 in the bleeder circuit 40 respectively, H10, H05, L05, L10 and L15; Second input then is electrically connected on the reference voltage Vref that reference voltage generator 30 is produced.That is to say that these six comparator compared is the dividing potential drop of each node of being connected with each comparator in the bleeder circuit 40 and the size of this reference voltage Vref.See through such mode, comparison circuit 50 can be used as an A/D conversion circuit, and the analog signal conversion that bleeder circuit is exported becomes suitable digital signal with control correction circuit 60.

The output of each comparator then is electrically connected on each the correction circuit unit 65 in the correction circuit 60 respectively in the comparison circuit 50.In the present embodiment, correction circuit 60 is capacitor arrays, comprises the correction circuit unit 65 of mutual parallel connection.These correction circuit unit 65 comprise a transistor S and as switch respectively and revise electric capacity Δ C; These conducting or open circuits as the transistor S of switch are then controlled by the output of corresponding comparator respectively.If the switching transistor S conducting of a certain correction circuit unit 65, then the electric capacity Δ C in this correction circuit unit 65 can be in parallel with the capacitor C f of filter circuit 70; Otherwise if this switching transistor S open circuit, then the electric capacity Δ C of this correction circuit unit 65 just can not be in parallel with the capacitor C f of filter circuit 70.

The operation principle of component error update the system 10 of the present invention, the caption of available Fig. 4.Fig. 4 is each node H15 among Fig. 3, H10, H05, T1, L05, the graph of a relation of the resistance relative error that resistance value that L10, L15 extremely hold and manufacturing process cause.Wherein the resistance relative error is the ratio that actual resistance departs from former design load, and for instance, when the resistance relative error was D (as 5%), actual resistance exceeded D (as precedent, promptly 5%) than former design load.In the ideal case, the resistance error that is caused by manufacturing process is 0, and the design of bleeder circuit 40 can make the dividing potential drop of node T1 just equate with reference voltage Vref; Because it is N: M that current generator 20 is supplied to the reference voltage generator 30 and the current ratio of bleeder circuit 40, have following relationship: M in node T1 between its total resistance value of extremely holding (R2+R3+R4+R5) and this reference resistance Rref this moment ^*(R2+R3+R3+R5)=N ^*(Rref).As shown in Figure 4, when the resistance relative error was 0, the all-in resistance between node T1 extremely holds just equaled (N/M) ^*Rref.In this case, the total resistance value nature between node L05, L10 and L15 extremely hold is less than (N/M) ^*Rref, this also represents node L05, the dividing potential drop of L10 and L15 is less than Vref.At this moment, be connected in node L05, the comparator of L10 and L15 is output as electronegative potential (because the dividing potential drop of three nodes is all less than Vref), makes all conductings of switch S of its control, and makes the electric capacity Δ C in the corresponding correction circuit unit 65 in parallel with the capacitor C f in this filter circuit 70.Relative, under above-mentioned situation, node H15, H10 and H05 to the total resistance value between ground then can be greater than (N/M) ^*Rref, that is to say, the dividing potential drop of node H15, H10 and H05 is all greater than Vref, cause three node H15 therewith, the comparator that H10 and H05 link to each other is output as high potential, thereby and make the switch S open circuit of its control, and the electric capacity Δ C in the corresponding correction circuit unit 65 just can not be in parallel with capacitor C f.Generally speaking, be that filter circuit 70 is Cf+3 Δ C with the total capacitance value of correction circuit 60 under 0 the situation at resistance error, and filter circuit 70 be the product of (Cf+3 Δ C) and Rf with the frequency range that correction circuit 60 forms.

The resistance that makes each resistance when the caused error of manufacturing process is during greater than the original design value, and the total resistance value between each node is extremely held also increases thereupon, shown in the skew lines of Fig. 4; But illustrated as the front that because of Rref one is arranged at the outer meeting resistance of integrated circuit outside, so its resistance value will not be subjected to the influence of integrated circuit fabrication process error; And two electric currents that current generator 20 is produced, its current ratio is not influenced by resistance error also, so (N/M) ^*Rref can be as a stable standard of comparison, shown in the horizontal dotted line among Fig. 4.If the caused error of manufacturing process is between Δ and 2 Δs, then the design of this bleeder circuit 40 can make the all-in resistance of node L05 between extremely holding greater than (N/M) ^*Rref.Dividing potential drop of this expression node H15, H10, H05 and L05 is all greater than Vref, and the comparator that links to each other with these nodes will make the switch S in the correction circuit unit 65 of its control all open a way, and the only surplus correction circuit unit 65 that is connected in node L10 and L15 is conducting.So when the resistance relative error was between Δ and 2 Δs, the total capacitance of filter circuit 70 and correction circuit 60 was Cf+2 Δ C.In other words, when error that manufacturing process caused makes its resistance value bigger than intrinsic resistance value, correction via component error correction circuit 10 of the present invention, filter circuit 70 can diminish relatively with the total capacitance value of correction circuit 60, so that the product of the resistance value of filter circuit 70 and correction circuit 60 and total capacitance value maintains in the permissible scope.

When node H15, H10, H05, L05, L10 and the L15 resistance value between ground changed with the increase and decrease of resistance relative error, the functional arrangement of Fig. 4 also can be divided into eight zones that are denoted as I to VIII respectively.In each zone, the conducting of the correction circuit unit 65 that the comparator that links to each other with each node is controlled and the situation of open circuit are then listed in Fig. 5.In Fig. 5, if the comparator that links to each other with certain node makes its corresponding correction circuit unit 65 conductings (closed), then be denoted as " opening ", represent switch S in this correction circuit unit for opening (ON); Not conducting then is denoted as " pass " if open a way (open), represents the switch S in this correction circuit unit to be pass (OFF).Please refer to Fig. 5.In area I, all conductings of correction circuit unit 65 make all electric capacity Δ C all in parallel with Cf, allow the total capacitance value of filter circuit 70 and correction circuit 60 become Cf+6 Δ C.Contrast Fig. 4 as can be known, this moment, the resistance value of resistance R _ f must be than more than little 3 Δs of former design load, so all correction circuit unit 65 all need be switched on by way of compensation in the correction circuit 60.

Same reason, in area I I, the resistance relative error is between-3 Δs and-2 Δs, and the total resistance value between only node H15 extremely holds is greater than (N/M) ^*Rref, the switch open circuit of its comparator control makes the filter circuit 70 and the total capacitance value of correction circuit 60 become Cf+5 Δ C.In area I II, the resistance relative error between-2 Δs and-Δ between, four correction circuit unit 65 conductings are arranged, make the total capacitance value of filter circuit 70 and correction circuit 60 become Cf+4 Δ C.

In regional VII, the resistance relative error only has a correction circuit unit 65 conductings between between 2 Δs and 3 Δs, becomes greatly owing to resistance R _ f is subjected to the manufacturing process error effect, and the total capacitance value of filter circuit 70 and correction circuit 60 is reduced to Cf+ Δ C.At last, in regional VIII, the resistance relative error surpasses 3 Δs, and all opening a way in all correction circuit unit 65, and makes the total capacitance value of filter circuit 70 and correction circuit 60 reduce to Cf.

Generally speaking, the characteristics of component error update the system 10 of the present invention are that it is the current generator 20 that is made of current mirror with, produces the output current of two equal proportions, respectively input reference voltage generator 30 and bleeder circuit 40.Because of the ratio of two electric currents is certain, the ratio of the reference voltage Vref that reference voltage generator 30 is produced and each dividing potential drop of bleeder circuit 40 can directly be converted to the ratio of two corresponding resistance; Otherwise the ratio of two corresponding resistance also can be exchanged into the ratio of voltage.Since the resistance R ref of reference voltage generator 30 is an outer meeting resistance, and the divider resistance of bleeder circuit 40 has identical resistance relative error with resistance R _ f in the filter circuit 70, each dividing potential drop in the reference voltage of comparison reference voltage generator 30 and the bleeder circuit 40, can understand in this integrated circuit, each resistance is because of resistance error that manufacturing process caused.The voltage difference that resistance error caused can be made corresponding circuit compensation via the control of the comparator in the comparison circuit 50 correction circuit 60.

Current generator in the component error update the system of the present invention is to be made of a current mirror.This current mirror is set up reference voltage in the reference voltage generator 30 and each dividing potential drop in the bleeder circuit 40 simultaneously with the electric current of fixed proportion.Such design makes the present invention not need must could set up the dividing potential drop that is used for comparison with a normal voltage and a bias voltage as prior art, and this advantage makes the present invention be used in portable type electronic product.Portable type electronic product, as mobile phone or notebook computer, many bias voltages of supplying integrated circuit in this electronic product with electric storage devices such as batteries.When electric weight that battery stored up is consumed gradually, bias voltage just may misalignment.Under the unstable situation of power supply supply, those dividing potential drops that need system's bias voltages to set up in addition to be used for comparison may be with regard to cisco unity malfunction with the prior art of correct work.Compared to prior art, in component error update the system of the present invention, the focus of current generator 20, provide the certain electric current of two ratios, the size of electric current can't have influence on the operation of this component error update the system, even the therefore bias voltage misalignment in the current mirror, component error update the system of the present invention still can be operated normally.

As previously mentioned, component error update the system 10 of the present invention is the resistance errors that compensate a filter circuit in the mode that changes capacitance.But the function of present embodiment is not limited thereto, as long as change the structure of correction circuit 60, the present invention can be applicable to other embodiment.In the present invention, the divider resistance of bleeder circuit 40 and the comparator that is mated and correction circuit unit 65 also can increase its number with the need, and to reach more accurate control, for example the percentage with Δ dwindles.If the manufacturing process error can be controlled in the certain limit, the number that also can reduce divider resistance and the comparator that is mated and correction circuit unit reduces cost.

The above only is preferred embodiment of the present invention, and all equivalences of being made in the application's claim scope change and revise, and all should belong to the covering scope of patent of the present invention.

Claims

1. A component error correction system, comprising:

A reference voltage generator, including an external resistor, electrically connected to an integrated circuit;

a voltage divider circuit comprising at least one series resistor formed on the integrated circuit;

a current generator, electrically connected to the reference voltage generator and the voltage divider circuit, for supplying current to the external resistor and the series resistor respectively, so that the reference voltage generator can generate a reference voltage at its output terminal and enabling the voltage divider circuit to produce a divided voltage at its output; and

A comparison circuit, electrically connected to the output terminal of the voltage dividing circuit, is used to compare the divided voltage generated by the voltage dividing circuit with the reference voltage to monitor whether there is an error in the resistance value of the series resistor of the voltage dividing circuit.

2. The device error correction system as claimed in claim 1, wherein the current generator provides a predetermined ratio between the current provided by the external resistor and the series resistor.

3. The component error correction system as claimed in claim 2, wherein the current generator is a current mirror, and the current mirror outputs current from two output terminals thereof to the external resistor and the series resistor respectively.

4. The component error correction system as claimed in claim 1, further comprising a correction circuit electrically connected to the comparison circuit for correcting component errors on the integrated circuit according to a comparison signal generated by the comparison circuit.

5. The component error correction system as claimed in claim 4, wherein the correction circuit comprises a correction element and a switch, the control terminal of the switch is electrically connected to the comparison circuit, and is used for determining the difference according to the comparison signal generated by the comparison circuit. Turn on or off the correction element.

6. The device error correction system as claimed in claim 5, wherein the correction device is a capacitor.

7. The component error correction system as claimed in claim 6, which is used to correct a filter circuit, the filter circuit is formed on the integrated circuit, electrically connected to the correction circuit in parallel, and the correction circuit is used for Correct component errors on the filter circuit.

8. The device error correction system as claimed in claim 7, wherein the filter circuit comprises a capacitive element and a resistive element, and the correction circuit is used to correct the product of the capacitance of the capacitive element and the resistance of the resistive element.

9. The component error correction system as claimed in claim 1, wherein the series resistors of the voltage divider circuit are electrically connected to each other in series, and each series resistor outputs a The voltages are divided so that the comparison circuit compares each divided voltage with the reference voltage.

10. The component error correction system as claimed in claim 9, wherein the comparison circuit includes at least one comparator, each comparator includes a first input end electrically connected to an output end of the voltage divider circuit for use in to receive the divided voltage from the output terminal of the voltage dividing circuit, and a second input terminal for inputting the reference voltage, wherein the comparator combines the divided voltage input by the first input terminal with the second input Comparing the reference voltage input by the comparator and outputting a corresponding comparison signal at the output terminal of the comparator.

11. A correction system for adjusting the bandwidth of an RC filter, the RC filter comprising a resistor and a capacitor array, the correction system comprising:

An external resistor, including a reference voltage terminal;

A voltage dividing circuit, including a voltage dividing terminal;

A current generator, respectively supplying equal proportions of current to the external resistor and the voltage dividing circuit, so that the reference voltage terminal of the external resistor generates a reference voltage, and the voltage dividing terminal of the voltage dividing circuit generates a divided voltage;

An analog/digital conversion circuit is used to compare the divided voltage with the reference voltage, and output a digital signal to control the capacitance array to generate different capacitance values.

12. The correction system as claimed in claim 11, wherein the current generator is a current mirror, and the two output terminals of the current mirror respectively output currents to the external resistor and the voltage divider circuit.

13. The correction system as claimed in claim 11, wherein a plurality of switches are respectively corresponding to each capacitor in the capacitor array, and the control terminals of the switches are electrically connected to the analog/digital conversion circuit for use according to the The digital signal generated by the analog/digital conversion circuit is used to turn on or off the switch.

14. The correction system as claimed in claim 13, wherein the voltage dividing circuit comprises a plurality of series resistors, each of which has a voltage dividing point, and the analog/digital conversion circuit compares the voltage of each voltage dividing point with the The reference voltage is used to output the digital signal to control the switch.

15. A correction system for adjusting an RC filter inside an integrated circuit, the RC filter comprising a resistor and a capacitor array, the correction system comprising:

an external resistor, set outside the integrated circuit, including a reference voltage terminal;

a voltage divider circuit, arranged inside the integrated circuit, composed of at least one series resistor, including a voltage divider terminal;

A current generator, respectively supplying equal proportions of current to the external resistance and the voltage dividing circuit, so that the reference voltage end of the external resistance generates a reference voltage, and the voltage dividing end of the voltage dividing circuit generates a divided voltage;

An analog/digital conversion circuit is used to compare the divided voltage with the reference voltage, and output different digital signals according to the change of the series resistance to control the capacitance array to generate different capacitance values.

16. The correction system as claimed in claim 15, wherein the current generator is a current mirror, and the two output terminals of the current mirror respectively output currents to the external resistor and the voltage divider circuit.

17. The correction system as claimed in claim 15, wherein a plurality of switches are respectively corresponding to each capacitor in the capacitor array, the control terminal of the switch is electrically connected to the analog/digital conversion circuit, and is used for according to the analog /Digital signal generated by the digital conversion circuit to turn on or off the switch.

18. The correction system as claimed in claim 17, wherein the voltage dividing circuit comprises a plurality of series resistors, each series resistance comprises a voltage dividing point, and the analog/digital conversion circuit compares the voltage of each voltage dividing point with the The reference voltage is used to output the digital signal to control the switch.