Resistance type burning and adjusting circuit structure, electronic equipment and burning and adjusting method

Abstract

The invention discloses a resistance type burning and adjusting circuit structure, electronic equipment and a burning and adjusting method, and aims to overcome the defect of low burning and adjusting precision of the existing resistance burning and adjusting technology. The structure comprises a resistor network module which is used for providing an adjustable resistance value and comprises three resistors connected in series and in parallel, and the resistor with the maximum resistance value is a burnt resistor; the adjusting assembly module is used for changing the equivalent resistance value of the resistor to be burnt and adjusted; and the probe interface module is used for providing a physical connection interface for external test equipment and an internal circuit. Aiming at the defects of a conventional burning and adjusting structure, a single resistor for determining the step length of a single step is changed into a mode of connecting three resistors in series and parallel, the step length is jointly determined by the three resistors, meanwhile, the resistor to be burnt and adjusted is designed to be the resistor with the large resistance value in the three resistors, and overcurrent damage caused by the fact that the single resistor is too small in the conventional structure is avoided.

Description

Technical Field

[0001] The present invention relates to the field of integrated circuit technology, and particularly relates to a resistive trimming circuit structure, an electronic device, and a trimming method. Background Art

[0002] In the field of integrated circuit technology, trimming is a commonly used parameter adjustment technique for calibrating key parameters in a circuit, such as voltage, current, and frequency. Currently, common trimming techniques mainly include antifuse trimming and resistive trimming. Antifuse trimming changes the circuit parameters by applying a high voltage or a large current to turn the antifuse from an open state to a short state. Resistive trimming achieves parameter calibration by adjusting the resistance value, and common methods include blowing a fuse and shunting a resistor with a diode. These techniques have been widely applied in circuits such as high-precision operational amplifiers and precision reference voltage sources. Their main function is to ensure that the circuit parameters reach the design target by adjusting the component values in the circuit, thereby improving the performance and reliability of the circuit.

[0003] However, there are some obvious deficiencies in the existing technologies. First, although antifuse trimming can achieve high precision, it requires applying a high voltage or a large current during the trimming process, which is likely to damage other components in the circuit, and the trimmed state is irreversible. Once the trimming is incorrect, it cannot be repaired. Second, traditional resistive trimming techniques, such as blowing a fuse and shunting a resistor with a diode, use the reverse breakdown of a diode (the overall resistance decreases) or a fuse (the overall resistance increases) to achieve resistor series-parallel connection. Although the operation is simple, the trimming step size is large, making it difficult to meet the requirements of high-precision circuits. In addition, existing trimming structures often introduce a large parasitic capacitance, affecting the frequency response and stability of the circuit. More importantly, there are significant defects in the trimming precision, overcurrent protection, and process compatibility of the existing technologies, making it difficult to meet the strict requirements for parameter adjustment in modern high-precision integrated circuits.

[0004] In summary, there is an urgent need for a new technical solution to solve the problems existing in the existing trimming technologies, such as insufficient trimming precision, high overcurrent risk, and large parasitic capacitance, to meet the growing demand for parameter adjustment in high-precision integrated circuits. Therefore, how to overcome the defects of low trimming precision, poor safety, and insufficient process compatibility in the existing integrated circuit technology has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a resistive trimming circuit structure, an electronic device, and a trimming method to overcome the deficiency of low trimming precision in the existing resistive trimming technology.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a resistive trimming circuit structure, comprising:

[0008] A resistor network module for providing an adjustable resistance value, including three series-parallel resistors, wherein the resistor with the largest resistance value is the resistor to be trimmed;

[0009] An adjustment component module for changing the equivalent resistance value of the resistor to be trimmed;

[0010] A probe interface module for providing a physical connection interface between an external test device and an internal circuit.

[0011] The resistor network module includes resistor R1, resistor R2, and resistor R3. After resistor R2 and resistor R3 are connected in series, they are then connected in parallel with resistor R1.

[0012] The adjustment component module is connected in parallel with the resistor to be trimmed.

[0013] The adjustment component module is a diode or a fuse.

[0014] The diode is configured to reduce the equivalent resistance value of the resistor to be trimmed when it undergoes reverse breakdown, and the fuse is configured to increase the equivalent resistance value of the resistor to be trimmed when it fuses.

[0015] The probe interface module includes two probe PADs, which are respectively connected to both ends of the adjustment component module.

[0016] In a second aspect, the present invention provides an electronic device, which includes the above-mentioned resistive trimming circuit structure.

[0017] In a third aspect, the present invention provides a trimming method, which is applied to the above-mentioned resistive trimming circuit structure, and the method includes:

[0018] S1, electrically connect an external trimming device to the resistor network module through the probe interface module;

[0019] S2, obtain a test signal corresponding to the current resistance value of the resistor network module;

[0020] S3, if the current resistance value is higher than the target value, send a trimming signal to the adjustment component module to reduce the equivalent resistance value of the resistor to be trimmed;

[0021] If the current resistance value is lower than the target value, send a trimming signal to the adjustment component module to increase the equivalent resistance value of the resistor to be trimmed;

[0022] S4, repeat S2 to S3 until the test signal corresponding to the current resistance value reaches the target value.

[0023] If the current resistance value in S3 is higher than the target value, a trimming signal is sent to the adjustment component module to reduce the equivalent resistance value of the resistor to be trimmed, including that if the current resistance value is higher than the target value, a trimming signal is sent to the adjustment component module through the probe interface module, causing the diode connected in parallel with the resistor to be trimmed to break down reversely, thereby reducing the equivalent resistance value of the resistor to be trimmed.

[0024] If the current resistance value in S3 is lower than the target value, a trimming signal is sent to the adjustment component module to increase the equivalent resistance value of the resistor to be trimmed, including that if the current resistance value is lower than the target value, a trimming signal is sent to the adjustment component module through the probe interface module, causing the fuse connected in parallel with the resistor to be trimmed to blow, thereby increasing the equivalent resistance value of the resistor to be trimmed.

[0025] Compared with the prior art, the present invention has the following beneficial technical effects:

[0026] The present invention provides a resistive trimming circuit structure, an electronic device and a trimming method, which effectively overcome the problem of insufficient precision in traditional resistor trimming technology. The resistor network module adopts a specific series-parallel structure of three resistors R1, R2, and R3, where R2, as the resistor to be trimmed, has the largest resistance value. This design, by maintaining a certain proportional relationship among R1, R2, and R3, when the step size decreases, it is necessary to increase the trimming resistor R2 instead of decreasing the trimming resistor in the traditional structure, thereby avoiding the overcurrent risk caused by the decrease of the trimming resistor with the decrease of the step size in the traditional structure. The adjustment component module is arranged in parallel with R2, and the equivalent resistance value of R2 is adjusted bidirectionally by the reverse breakdown of the diode or the blowing of the fuse. When the diode breaks down, it provides a low-resistance bypass to reduce the total resistance value, and when the fuse blows, it cuts off the R2 branch to increase the total resistance value. The two adjustment methods are respectively aimed at the resistance value adjustment requirements in different directions. The two PADs of the probe interface module are respectively used for controlling signal input and test signal output, forming a complete closed-loop adjustment system. In the trimming method, by real-time monitoring the resistance value and comparing it with the target value, the adjustment method of diode breakdown or fuse blowing is intelligently selected, and an iterative approximation strategy is adopted to gradually reduce the deviation. The combination of this structure and method design not only ensures the reliability of the adjustment process, but also realizes more precise step size control through the collaborative action of multiple resistors, and finally significantly improves the trimming precision. After integrating this structure into the electronic device, the adjustable range and adjustment precision of its key circuit parameters are significantly improved, solving the problem of limited precision caused by overcurrent risk and parasitic effects in the traditional single-resistor trimming structure. Description of the Drawings

[0027] Figure 1 It is a schematic diagram of a conventional trimming structure in an embodiment of the present invention.

[0028] Figure 2 It is a schematic diagram of a resistive trimming circuit structure in an embodiment of the present invention.

[0029] Figure 3 Schematic diagram of a burning adjustment method flow in an embodiment of the present invention.

[0030] Figure 4 Schematic diagram of a 4-2-1 code burning adjustment structure in an embodiment of the present invention.

[0031] Figure 5 Schematic diagram of an application scenario of a resistive burning adjustment circuit structure in an embodiment of the present invention. Detailed implementation manners

[0032] General high-performance semiconductor integrated circuits are widely used in the field of integrated circuit technology. Their performance levels directly affect the theoretical initial accuracy of electronic systems. The independent research and development and iterative upgrading of high-precision semiconductor integrated circuits are particularly important.

[0033] Currently, for most high-performance devices such as high-precision operational amplifiers and precision references, in order to reduce costs and avoid the risk of parameter accuracy drift caused by process fluctuations, a burning adjustment network needs to be set at the nodes affecting key parameters. Generally, a conventional burning adjustment structure of a resistor in parallel with a diode is adopted, as shown in Figure 1 (a), or a burning adjustment structure of a resistor in parallel with a fuse is adopted, as shown in Figure 1 (b). The resistance series-parallel connection is realized by the reverse breakdown of the diode (the overall resistance decreases) or the fuse (the overall resistance increases). The conventional burning adjustment structure is shown in Figure 1 As shown. Its burning adjustment step size is completely determined by the designed size of the burning adjustment resistor value. The smaller the resistance value, the smaller the step size, and the higher the burning adjustment accuracy of the device. However, the current passing through the corresponding resistor and the probe will linearly increase as the resistance decreases. The larger current will damage precision consumables such as probes. At the same time, in order to avoid damaging the resistor body, the resistor area needs to be increased several times in the layout design, which will further introduce effects such as a large parasitic capacitance and further affect the device parameter accuracy. Therefore, the conventional burning adjustment structure often cannot meet the design requirements of precision devices.

[0034] The present invention is proposed based on such a background, aiming to provide a high-precision resistive burning adjustment circuit structure and its design method. Through innovative resistor network design and step size control technology, a more accurate and safer burning adjustment process can be realized, while reducing the influence of parasitic capacitance and improving the performance and reliability of the circuit.

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] In addition, the terms "first" and "second" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a number of" means two or more, unless otherwise specifically defined.

[0037] Referring to Figure 2 The following shows a specific embodiment of a resistive trimming circuit structure provided by the present invention, which is divided into Figure 2 the diode type as shown in Figure 2 (a) and the fuse type as shown in

[0038]

[0039]

[0040]

[0041] a resistor network module for providing an adjustable resistance value, including three series-parallel resistors, where the resistor with the largest resistance value is the resistor to be trimmed;

[0042] an adjustment component module for changing the equivalent resistance value of the resistor to be trimmed;

[0043] a probe interface module for providing a physical connection interface between an external test device and an internal circuit.

[0044] Specifically, the resistor network module includes resistor R1, resistor R2, and resistor R3. After resistor R2 and resistor R3 are connected in series, they are then connected in parallel with resistor R1. The adjustment component module is connected in parallel with the resistor to be trimmed. Among them, R2 is the resistor to be trimmed, and its resistance value is greater than that of R1 and R3. R1, R2, and R3 maintain a certain proportional relationship. When the resistance value needs to be adjusted, R1 and R3 will change synchronously with R2, so as to ensure that the step size of each adjustment remains stable. At the same time, R2 is always the maximum value among the three resistors, avoiding the drawback of insufficient trimming accuracy caused by the control of a single resistor in the traditional structure.

[0044] The adjustment component module is a diode or a fuse. The diode is configured to reduce the equivalent resistance value of the trimmed resistor when it undergoes reverse breakdown, and the fuse is configured to increase the equivalent resistance value of the trimmed resistor when it fuses.

[0045] The probe interface module includes two symmetric probe PADs, namely probe PAD A and probe PAD B, which are respectively connected to both ends of the adjustment component module. These two PADs are functionally completely equivalent, and the input and output functions can be flexibly configured according to actual needs.

[0046] Among them, in this specific embodiment, it is preferably when the adjustment component module is a diode, probe PAD A is connected to the cathode of the diode, and probe PAD B is connected to the anode of the diode.

[0047] This specific embodiment of the present invention also provides an electronic device, which includes the above-mentioned resistive trimming circuit structure. It should be noted that the above-mentioned resistive trimming circuit structure is a single-group structure. In actual applications, multiple groups of resistive trimming circuit structures can be connected in the electronic device to jointly perform the trimming work.

[0048] The resistive trimming circuit structure provided by the present invention demonstrates significant technical advantages in electronic devices such as operational amplifiers. In a specific embodiment, the electronic device can be an operational amplifier. When a traditional operational amplifier adopts a single-resistor trimming structure, limited by the resistor accuracy and current limit, the minimum trimming step can only reach ±30 μV, resulting in the offset voltage of some chips not being fully calibrated, seriously affecting the common-mode rejection ratio and signal processing accuracy of the amplifier. After adopting the three-resistor series-parallel network structure of the present invention, by optimizing the resistance ratio of R1, R2, and R3 and combining the "4-2-1" code step-by-step approximation algorithm, the minimum trimming step is successfully reduced to ±7.5 μV, improving the input offset voltage calibration accuracy of the operational amplifier by 4 times.

[0049] In actual mass production testing, the advantages of this technology are more prominent. Due to insufficient accuracy of the traditional trimming method, approximately 60%-70% of the chips cannot pass the calibration test, and the medium-test yield has long remained at a low level of 30%-40%. After adopting the present invention, the yield breaks through 80% through the following improvements: the design of the large-value R2 significantly reduces the trimming current, avoiding overcurrent damage to the probes and resistors; the closed-loop feedback trimming algorithm can automatically compensate for parameter deviations caused by process fluctuations. These improvements ensure a stable trimming effect even in the presence of process deviations.

[0050] This invention can be widely applied to the trimming structure design of various precision devices, and has characteristics such as a simple circuit structure and a safe and reliable trimming process.

[0051] The present invention also provides a trimming method applied to the resistive trimming circuit structure, such asFigure 3 As shown in the figure, it includes:

[0052] S1, electrically connect an external burning and adjusting device to a resistor network module through a probe interface module;

[0053] S2, obtain a test signal corresponding to the current resistance value of the resistor network module;

[0054] S3, if the current resistance value is higher than the target value, send a burning and adjusting signal to the adjusting component module to reduce the equivalent resistance value of the resistor to be burned and adjusted;

[0055] If the current resistance value is lower than the target value, send a burning and adjusting signal to the adjusting component module to increase the equivalent resistance value of the resistor to be burned and adjusted;

[0056] S4, repeat S2 to S3 until the test signal corresponding to the current resistance value reaches the target value.

[0057] Specifically, in S3, to reduce the equivalent resistance value of the resistor to be burned and adjusted, the reverse breakdown of a diode is adopted. A burning and adjusting signal is sent to the adjusting component module through the probe interface module, so that the diode connected in parallel with the resistor to be burned and adjusted undergoes reverse breakdown, reducing the equivalent resistance value of the resistor to be burned and adjusted. In this specific embodiment, a pulse is applied to PAD A to cause the diode to break down and form a low-resistance path.

[0058] Similarly, in S3, to increase the equivalent resistance value of the resistor to be burned and adjusted, the fuse is melted. A burning and adjusting signal is sent to the adjusting component module through the probe interface module, so that the fuse connected in parallel with the resistor to be burned and adjusted is melted, increasing the equivalent resistance value of the resistor to be burned and adjusted. In this specific embodiment, current is injected into PAD A to heat the fuse and cut off the R2 branch.

[0059] To make the technical solution of the present invention easier to understand, next, in combination with an actual burning and adjusting scenario, the calculation method and design process of the resistance value change of the burning and adjusting structure will be explained.

[0060] The burning and adjusting step ΔV is designed according to the product parameter characteristics. Assuming that the current flowing through the burning and adjusting network remains unchanged, ΔV is related to the resistance change amount ΔR. The smaller ΔR is, the smaller ΔV is, and the higher the burning and adjusting accuracy is. Figure 2 For the high-precision burning and adjusting structure shown, the calculation method of the resistance change amount ΔR and the resistance value design scheme are as follows:

[0061]

[0062] For convenience of design, let R2 = k(R1 + R3), then

[0063]

[0064] For further simplification, let k = 1, then

[0065]

[0066] Next, a multi-step trimming resistance design is carried out. Since the trimming range covered by the "8, 4, 2, 1" trimming step design method is relatively large, based on the "8, 4, 2, 1" trimming step design method, with R1 as the reference resistance, for the trimming step number n (n≥1): Let R3 = (2 n-1 -1)×R1, which can make

[0067]

[0068] When n = 1, R3 = (2 n-1 -1)×R1 = 0, R2 = R1 + R3 = R1

[0069] When n = 2, R3 = R1, R2 = 2×R1

[0070] When n = 3, R3 = 3×R1, R2 = 4×R1

[0071] Based on the above design method, the resistance change ΔR is determined by 2 n and R1. The larger n or the smaller R1, the smaller ΔR, the smaller the corresponding trimming step size, and the higher the trimming accuracy. The larger n means the higher the trimming accuracy, but the trimmed resistor R2 is larger, which can avoid the drawback of excessive current caused by a single resistor determining the step size in the conventional structure.

[0072] When R1 = R, the 4, 2, 1 code trimming structure composed of n = 1, n = 2, and n = 3 is as Figure 4 shown, and its ΔR are respectively

[0073] Generally, 4-step trimming can achieve the 8, 4, 2, 1 code. For the Figure 4 shown 4, 2, 1 code trimming structure, adding one step with ΔR = R can achieve the 8, 4, 2, 1 code trimming, which can meet the trimming requirements of most analog integrated circuits. When designing, the trimming step number can also be increased according to the actual situation to obtain a higher-precision trimming structure.

[0074] Taking a high-precision operational amplifier circuit as an example, since the conventional trimming structure is adopted in this operational amplifier, the trimming step size is relatively large, resulting in difficulty in adjusting the input offset voltage of some chips to the target range through trimming, and the yield of the middle test is low. The trimming step size of this product To reduce the step size, it is necessary to reduce the trimming resistor to reduce the change amount ΔR. Since the trimming current will increase linearly with the decrease of the resistor, there is a risk of overcurrent damage. At the same time, it is necessary to increase the resistor area, and the larger resistor area introduces a larger parasitic capacitance.

[0075] Accordingly, based on the resistive trimming circuit structure provided by the present invention, the trimming structure of the circuit is redesigned. Referring to Figure 5 as shown, where ΔR0 = 1.625R is the compensation resistor to achieve symmetry of the total resistance on both sides. After the redesign, the minimum trimming step of this operational amplifier is reduced to 1 / 4 of the original, improving the trimming accuracy. The yield of in-process testing is increased to more than twice the original, bringing considerable economic benefits.

[0076] Through the innovative design of the resistive trimming circuit structure and the trimming method, the present invention effectively solves the problems of low accuracy, poor safety, and insufficient process compatibility in traditional integrated circuit trimming technology. The resistor network module adopts a series-parallel structure of three resistors R1, R2, and R3, where the largest resistor R2 is the main body to be trimmed. This design significantly reduces the overcurrent risk through a distributed current path, and the operating current can be reduced by more than 60% compared with the traditional single-resistor structure. The adjustment component module adopts a diode or fuse in parallel with R2. The breakdown of the diode can achieve precise fine-tuning of the resistance value reduction, and the melting of the fuse supports precise adjustment of the resistance value increase. The cooperation of the two reduces the minimum trimming step from ±30 μV to ±7.5 μV, and the accuracy is improved by 4 times. The dual-PAD design of the probe interface module realizes the control of the trimming process, and the two equivalent probe PADs can be configured and connected according to actual needs to ensure the accuracy of parameter calibration. In terms of process compatibility, all components can be manufactured using standard processes. The diode can be a conventional diode or a Zener diode, and the fuse can be an aluminum wire connection or a polysilicon structure, without special processes or additional mask layers. The trimming method uses an iterative process of "measurement - judgment - adjustment - verification" and combines multi-step trimming to gradually approach the target value of the resistance value, improving the yield of in-process testing from 30 - 40% to more than 80% while ensuring safety. The resistive trimming circuit structure design provided by the present invention enables the trimming step to be reduced according to requirements, improving the trimming accuracy, thereby increasing the yield of in-process testing and balancing the requirements of accuracy, safety, and process.

[0077] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A resistive burn-in circuit structure, characterized in that Comprising: A resistor network module for providing an adjustable resistance value, including 3 series-parallel resistors, where the resistor with the largest resistance value is the burnt-adjustable resistor; An adjustment component module for changing the equivalent resistance value of the burnt-adjustable resistor; A probe interface module for providing a physical connection interface between an external test device and an internal circuit.

2. The resistive burn-in circuit structure according to claim 1, wherein The resistor network module includes resistor R1, resistor R2, and resistor R3. After resistor R2 and resistor R3 are connected in series, they are then connected in parallel with resistor R1.

3. A resistive burn-in circuit structure according to claim 1, characterized in that The adjustment component module is connected in parallel with the burnt-adjustable resistor.

4. A resistive burn-in circuit structure according to claim 1, characterized in that The adjustment component module is a diode or a fuse.

5. A resistive burn-in circuit structure according to claim 4, characterized in that, The diode is configured to reduce the equivalent resistance value of the burnt-adjustable resistor when reverse breakdown occurs, and the fuse is configured to increase the equivalent resistance value of the burnt-adjustable resistor when it melts.

6. The resistive burn-in circuit structure according to claim 1, wherein, The probe interface module includes two probe PADs, which are respectively connected to both ends of the adjustment component module.

7. An electronic device, characterized in that, Including the resistive burn-in circuit structure according to any one of claims 1 to 6.

8. A cooking method, characterized in that, Applied to a resistive burn-in circuit structure according to claim 1, the method includes: S1, electrically connecting an external burn-in device to the resistor network module through the probe interface module; S2, obtaining a test signal corresponding to the current resistance value of the resistor network module; S3, if the current resistance value is higher than the target value, sending a burn-in signal to the adjustment component module to reduce the equivalent resistance value of the burnt-adjustable resistor; if the current resistance value is lower than the target value, sending a burn-in signal to the adjustment component module to increase the equivalent resistance value of the burnt-adjustable resistor; S4, repeating S2 to S3 until the test signal corresponding to the current resistance value reaches the target value.

9. A cooking method according to claim 8, characterized in that, In S3, the statement that if the current resistance value is higher than the target value, sending a burn-in signal to the adjustment component module to reduce the equivalent resistance value of the burnt-adjustable resistor includes that if the current resistance value is higher than the target value, sending a burn-in signal to the adjustment component module through the probe interface module to cause the diode connected in parallel with the burnt-adjustable resistor to reverse breakdown, thereby reducing the equivalent resistance value of the burnt-adjustable resistor.

10. A cooking method according to claim 8, characterized in that, In S3, the statement that if the current resistance value is lower than the target value, sending a burn-in signal to the adjustment component module to increase the equivalent resistance value of the burnt-adjustable resistor includes that if the current resistance value is lower than the target value, sending a burn-in signal to the adjustment component module through the probe interface module to cause the fuse connected in parallel with the burnt-adjustable resistor to melt, thereby increasing the equivalent resistance value of the burnt-adjustable resistor.

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