CN217954989U - An input bias current compensation circuit and oscilloscope - Google Patents
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Abstract
本实用新型公开了一种输入偏流补偿电路及示波器。该输入偏流补偿电路，包括：输入晶体管，所述输入晶体管的基极用于采集输入信号；补偿晶体管，所述补偿晶体管与所述输入晶体管串联连接；电流镜，所述电流镜与所述输入晶体管的基极电连接，以及所述电流镜与所述补偿晶体管的基极电连接；所述电流镜用于将所述补偿晶体管的基极电流镜像至所述输入晶体管的基极，以补偿所述输入晶体管的基极偏流。本实用新型实施例通过设置补偿晶体管和电流镜，弥补了输入晶体管基极产生的输入偏流对测量产生的影响，提高了测量的精准度。
The utility model discloses an input bias current compensation circuit and an oscilloscope. The input bias current compensation circuit includes: an input transistor, the base of which is used to collect input signals; a compensation transistor, which is connected in series with the input transistor; a current mirror, which is connected to the input The base of the transistor is electrically connected, and the current mirror is electrically connected to the base of the compensation transistor; the current mirror is used to mirror the base current of the compensation transistor to the base of the input transistor to compensate base bias current of the input transistor. The embodiment of the utility model compensates for the influence of the input bias current generated by the base of the input transistor on the measurement by setting the compensation transistor and the current mirror, thereby improving the accuracy of the measurement.
Description
技术领域technical field
本实用新型涉及电路技术领域，尤其涉及一种输入偏流补偿电路及示波器。The utility model relates to the technical field of circuits, in particular to an input bias current compensation circuit and an oscilloscope.
背景技术Background technique
示波器是一种用来测量交流电或脉冲电流波形的仪器。其能够将电信号转换成看得见的图像，凡可以变为电效应的周期性物理过程都可以用示波器进行观测，便于人们研究各种电现象的变化过程。An oscilloscope is an instrument used to measure alternating current or pulse current waveforms. It can convert electrical signals into visible images, and all periodic physical processes that can be transformed into electrical effects can be observed with an oscilloscope, which is convenient for people to study the changing process of various electrical phenomena.
在现有技术中，示波器工作时的功放功能由晶体管完成，但晶体管的基区中载流子的扩散与复合会形成相应的复合电流，即基极电流。In the prior art, the power amplifier function of the oscilloscope is completed by the transistor, but the diffusion and recombination of carriers in the base region of the transistor will form a corresponding recombination current, that is, the base current.
因此，当晶体管作为示波器的输入晶体管时，会产生输入偏流，这会导致被测试点的电压产生偏移，从而对示波器的测量准确性产生影响。Therefore, when the transistor is used as the input transistor of the oscilloscope, an input bias current will be generated, which will cause the voltage of the point under test to deviate, thereby affecting the measurement accuracy of the oscilloscope.
实用新型内容Utility model content
本实用新型提供了一种输入偏流补偿电路及示波器，以补偿输入晶体管的输入偏流，提升示波器的测量准确性。The utility model provides an input bias current compensation circuit and an oscilloscope to compensate the input bias current of an input transistor and improve the measurement accuracy of the oscilloscope.
根据本实用新型的一方面，提供了一种输入偏流补偿电路，包括：According to an aspect of the present invention, an input bias current compensation circuit is provided, including:
输入晶体管，所述输入晶体管的基极用于采集输入信号；an input transistor, the base of which is used for collecting input signals;
补偿晶体管，所述补偿晶体管与所述输入晶体管串联连接；a compensation transistor connected in series with the input transistor;
电流镜，所述电流镜与所述输入晶体管的基极电连接，以及所述电流镜与所述补偿晶体管的基极电连接；所述电流镜用于将所述补偿晶体管的基极电流镜像至所述输入晶体管的基极，以补偿所述输入晶体管的基极偏流。a current mirror, the current mirror is electrically connected to the base of the input transistor, and the current mirror is electrically connected to the base of the compensation transistor; the current mirror is used to mirror the base current of the compensation transistor to the base of the input transistor to compensate for the base bias current of the input transistor.
可选地，所述电流镜为镜像比例可调电流镜，所述电流镜的镜像比例为设定值。Optionally, the current mirror is an adjustable mirror ratio current mirror, and the mirror ratio of the current mirror is a set value.
可选地，所述补偿晶体管、所述输入晶体管和所述电流镜集成于同一芯片中。Optionally, the compensation transistor, the input transistor and the current mirror are integrated in the same chip.
可选地，所述补偿晶体管与所述输入晶体管之间的距离小于预设距离。Optionally, the distance between the compensation transistor and the input transistor is smaller than a preset distance.
可选地，输入偏流补偿电路还包括：Optionally, the input bias current compensation circuit further includes:
阻抗隔离模块，所述阻抗隔离模块串联于所述输入晶体管的基极和所述电流镜之间；所述阻抗隔离模块用于和输入端进行阻抗隔离。An impedance isolation module, the impedance isolation module is connected in series between the base of the input transistor and the current mirror; the impedance isolation module is used for impedance isolation from the input terminal.
可选地，所述阻抗隔离模块包括：第一电阻，所述第一电阻串联于所述输入晶体管的基极和所述电流镜之间；Optionally, the impedance isolation module includes: a first resistor connected in series between the base of the input transistor and the current mirror;
或者，所述阻抗隔离模块包括：第一电流缓冲器，所述第一电流缓冲器串联于所述输入晶体管的基极和所述电流镜之间，所述第一电流缓冲器的偏置端接入第一偏置电压。Alternatively, the impedance isolation module includes: a first current buffer, the first current buffer is connected in series between the base of the input transistor and the current mirror, and the bias terminal of the first current buffer Connect to the first bias voltage.
可选地，输入偏流补偿电路还包括：Optionally, the input bias current compensation circuit further includes:
工作点稳定模块，所述工作点稳定模块串联于所述补偿晶体管的基极和所述电流镜之间；所述工作点稳定模块用于稳定所述输入晶体管和所述补偿晶体管的直流工作点以及对所述输入端进行阻抗隔离。An operating point stabilizing module, the operating point stabilizing module is connected in series between the base of the compensation transistor and the current mirror; the operating point stabilizing module is used to stabilize the DC operating points of the input transistor and the compensation transistor and performing impedance isolation on the input terminal.
可选地，所述工作点稳定模块包括：第二电阻，所述第二电阻串联于所述补偿晶体管的基极和所述电流镜之间；Optionally, the operating point stabilization module includes: a second resistor connected in series between the base of the compensation transistor and the current mirror;
或者，所述工作点稳定模块包括：第二电流缓冲器，所述第二电流缓冲器串联于所述补偿晶体管的基极和所述电流镜之间，所述第二电流缓冲器的偏置端接入第二偏置电压；Alternatively, the operating point stabilization module includes: a second current buffer, the second current buffer is connected in series between the base of the compensation transistor and the current mirror, and the bias of the second current buffer The terminal is connected to the second bias voltage;
或者，所述工作点稳定模块包括：二极管，所述二极管串联于所述补偿晶体管的基极和所述电流镜之间。Alternatively, the working point stabilizing module includes: a diode connected in series between the base of the compensation transistor and the current mirror.
可选地，所述输入晶体管和所述补偿晶体管均为三极管；Optionally, both the input transistor and the compensation transistor are triodes;
所述电流镜采用的晶体管为场效应管和/或三极管。The transistors used in the current mirror are field effect transistors and/or triodes.
根据本实用新型的另一方面，提供了一种示波器，包括：以上任一实施例所述的输入偏流补偿电路；其中，所述输入晶体管的基极作为所述示波器的输入端。According to another aspect of the present invention, an oscilloscope is provided, comprising: the input bias current compensation circuit described in any one of the above embodiments; wherein, the base of the input transistor is used as an input terminal of the oscilloscope.
本实用新型实施例的技术方案，采用输入晶体管、补偿晶体管与电流镜组合的方案，补偿晶体管的基极与电流镜的一端连接，输入晶体管的基极与电流镜的另一端连接。补偿晶体管的基极电流流入电流镜，电流镜将补偿晶体管的基极电流“复制”，电流镜将“复制”的电流通过另一端输出至输入晶体管的基极，用于补偿输入晶体管基极的输入偏流。因此，本实用新型实施例减少了输入晶体管基极产生的输入偏流对测量产生的影响，提高测量的精准度。The technical scheme of the embodiment of the utility model adopts the combination scheme of the input transistor, the compensation transistor and the current mirror, the base of the compensation transistor is connected to one end of the current mirror, and the base of the input transistor is connected to the other end of the current mirror. The base current of the compensation transistor flows into the current mirror, the current mirror "copy" the base current of the compensation transistor, and the current mirror outputs the "copied" current to the base of the input transistor through the other end, which is used to compensate the base current of the input transistor Input bias current. Therefore, the embodiment of the utility model reduces the influence of the input bias current generated by the base of the input transistor on the measurement, and improves the measurement accuracy.
应当理解，本部分所描述的内容并非旨在标识本实用新型的实施例的关键或重要特征，也不用于限制本实用新型的范围。本实用新型的其它特征将通过以下的说明书而变得容易理解。It should be understood that the content described in this section is not intended to identify key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other characteristics of the present invention will be easily understood through the following description.
附图说明Description of drawings
为了更清楚地说明本实用新型实施例中的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本实用新型的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some implementations of the present invention. For example, those of ordinary skill in the art can also obtain other drawings based on these drawings on the premise of not paying creative efforts.
图1是本实用新型实施例提供的一种输入偏流补偿电路的结构示意图；Fig. 1 is a schematic structural diagram of an input bias current compensation circuit provided by an embodiment of the present invention;
图2是本实用新型实施例提供的另一种输入偏流补偿电路的结构示意图；Fig. 2 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention;
图3是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图；Fig. 3 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention;
图4是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图；Fig. 4 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention;
图5是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图；Fig. 5 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention;
图6是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图；FIG. 6 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention;
图7是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图；Fig. 7 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention;
图8是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图。FIG. 8 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention.
具体实施方式Detailed ways
为了使本技术领域的人员更好地理解本实用新型方案，下面将结合本实用新型实施例中的附图，对本实用新型实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本实用新型一部分的实施例，而不是全部的实施例。基于本实用新型中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都应当属于本实用新型保护的范围。In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the utility model. Obviously, the described The embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.
需要说明的是，本实用新型的说明书和权利要求书及上述附图中的术语“第一”、“第二”等是用于区别类似的对象，而不必用于描述特定的顺序或先后次序。应该理解这样使用的数据在适当情况下可以互换，以便这里描述的本实用新型的实施例能够以除了在这里图示或描述的那些以外的顺序实施。此外，术语“包括”和“具有”以及他们的任何变形，意图在于覆盖不排他的包含，例如，包含了一系列步骤或单元的过程、方法、系统、产品或设备不必限于清楚地列出的那些步骤或单元，而是可包括没有清楚地列出的或对于这些过程、方法、产品或设备固有的其它步骤或单元。It should be noted that the terms "first" and "second" in the specification and claims of the present utility model and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific order or sequence . It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or device comprising a sequence of steps or elements is not necessarily limited to the expressly listed instead, may include other steps or elements not explicitly listed or inherent to the process, method, product or apparatus.
图1是本实用新型实施例提供的一种输入偏流补偿电路的结构示意图。参照图1，该输入偏流补偿电路包括：FIG. 1 is a schematic structural diagram of an input bias current compensation circuit provided by an embodiment of the present invention. Referring to Figure 1, the input bias current compensation circuit includes:
输入晶体管Q1，输入晶体管Q1的基极用于采集输入信号；Input transistor Q1, the base of the input transistor Q1 is used to collect the input signal;
补偿晶体管Q2，补偿晶体管Q2与输入晶体管Q1串联连接；Compensation transistor Q2, the compensation transistor Q2 is connected in series with the input transistor Q1;
电流镜110，电流镜110与输入晶体管Q1的基极电连接，以及电流镜110与补偿晶体管Q2的基极电连接；电流镜110用于将补偿晶体管Q2的基极电流镜像至输入晶体管Q1的基极，以补偿输入晶体管Q1的基极偏流。A
具体地，输入晶体管Q1为示波器的检测端晶体管，即输入晶体管Q1的基极用于连接被测试点。输入晶体管Q1工作时其基极产生较小的电流(即输入偏流)，该电流抽取自被测试点，从而会影响被测试点电压，影响测量准确性。本实用新型实施例通过设置补偿晶体管Q2和电流镜110能够对输入晶体管Q1的输入级进行电流补偿，以弥补抽取电流对测量产生的影响。电流镜110是模拟集成电路中普遍存在的一种标准部件，其特点是输出电流是对输入电流按一定比例的“复制”。Specifically, the input transistor Q1 is a detection terminal transistor of the oscilloscope, that is, the base of the input transistor Q1 is used to connect the point to be tested. When the input transistor Q1 is working, its base generates a small current (namely input bias current), which is drawn from the point under test, thus affecting the voltage of the point under test and affecting the measurement accuracy. In the embodiment of the present invention, by setting the compensation transistor Q2 and the
可选地，输入晶体管Q1和补偿晶体管Q2均为三极管；电流镜110采用的晶体管为场效应管和/或三极管。Optionally, both the input transistor Q1 and the compensation transistor Q2 are triodes; the transistors used in the
示例性地，本实用新型实施例对输入偏流进行补偿的原理为：输入晶体管Q1和补偿晶体管Q2位于同一电流通路中，因此，当输入晶体管Q1的基极接入被测试点电压而产生电流时，补偿晶体管Q2也会随之产生电流。与输入晶体管Q1类似，补偿晶体管Q2的基极也会产生较小的电流，该较小的电流通过电流镜110镜像至输入晶体管Q1的基极。由此可见，流入输入晶体管Q1的基极的电流通路有两条，一条为被测试点的电流路径，另一条为电流镜110的电流路径。与现有技术中输入晶体管Q1的基极电流仅由被测试点提供相比，本实用新型实施例增加了电流镜110对输入晶体管Q1的基极电流进行补偿，从而减小了从被测试点抽取的电流。在理想状态下，当电流镜110的电流路径的电流等于输入晶体管Q1的基极电流时，从被测试点抽取的电流为0。Exemplarily, the principle of compensating the input bias current in this embodiment of the utility model is: the input transistor Q1 and the compensation transistor Q2 are located in the same current path, therefore, when the base of the input transistor Q1 is connected to the voltage of the point under test to generate current , the compensation transistor Q2 will also generate current accordingly. Similar to the input transistor Q1 , the base of the compensation transistor Q2 also generates a small current, which is mirrored to the base of the input transistor Q1 by the
因此，本发明实施例在输入偏流补偿电路中设置补偿晶体管Q2和电流镜110，能够补偿输入晶体管Q1的基极偏流，从而提高了测量的精准度。Therefore, in the embodiment of the present invention, the compensation transistor Q2 and the
可选地，在上述实施例的基础上，电流镜110为镜像比例可调电流镜，电流镜110的镜像比例为设定值。Optionally, on the basis of the above embodiments, the
本发明实施例中使用的电流镜110为比例可调电流镜，其可以根据设定的比例输出相应的电流。通过使用比例可调节电流镜，在输入晶体管Q1的基极电流和补偿晶体管Q2的基极电流存在差异时，也可以通过设定比例镜像补偿晶体管Q2的基极电流，补偿输入晶体管Q1的基极电流。这样的设置减小了晶体管间差异带来的影响，有利于设置从被测试点抽取的电流为0，进一步提升测量的准确性。The
可选地，在上述实施例的基础上，补偿晶体管Q2、输入晶体管Q1和电流镜110集成于同一芯片中,可以在相同的工艺中制备而成，各晶体管的工艺误差比较接近，有利于提升工艺精度，提升测量精度。示例性地，输入晶体管Q1和补偿晶体管Q2是相同型号的晶体管，尺寸和大小相等，电流镜110的镜像比例为1：1，也能起到较好的补偿效果。这样的设置可以缩小输入偏流补偿电路的体积，使其可以应用在空间有限的环境中，扩大使用场景。Optionally, on the basis of the above-mentioned embodiments, the compensation transistor Q2, the input transistor Q1 and the
可选地，在上述实施例的基础上，补偿晶体管Q2与输入晶体管Q1之间的距离小于预设距离。具体地，预设距离可以根据需要进行设定，以使补偿晶体管Q2与输入晶体管Q1在芯片上的位置十分接近。这样的设置使得在芯片加工时，补偿晶体管Q2与输入晶体管Q1可以处于相同的温度环境中，其受工艺波动影响较小，以降低工艺和温度误差带来的影响。Optionally, based on the above embodiments, the distance between the compensation transistor Q2 and the input transistor Q1 is smaller than a preset distance. Specifically, the preset distance can be set as required, so that the positions of the compensation transistor Q2 and the input transistor Q1 on the chip are very close. Such setting enables the compensation transistor Q2 and the input transistor Q1 to be in the same temperature environment during chip processing, which is less affected by process fluctuations, so as to reduce the impact of process and temperature errors.
图2是本实用新型实施例提供的另一种输入偏流补偿电路的结构示意图。参照图2，该输入偏流补偿电路还包括：FIG. 2 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention. Referring to Figure 2, the input bias current compensation circuit also includes:
阻抗隔离模块210，阻抗隔离模块210串联于输入晶体管Q1的基极和电流镜110之间；阻抗隔离模块210用于和输入端进行阻抗隔离。输入阻抗是电路中输入端的等效阻抗，输入阻抗反映了对电流阻碍作用的大小。阻抗隔离是将上一级电路与下一级电路接入阻抗，使两级电路隔离开，降低两级电路间的影响。在电流镜110与输入晶体管Q1的基极间串联阻抗隔离模块210，相当于增加了电路的输入阻抗，从而进行阻抗隔离。这样的设置可以减少电流镜110对输入晶体管Q1输入级特性的影响。An
图3是本实用新型实施例提供又一种输入偏流补偿电路的结构示意图。FIG. 3 is a schematic structural diagram of another input bias current compensation circuit provided by the embodiment of the present invention.
图4是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图。结合图3和图4，阻抗隔离模块210包括：第一电阻R1，第一电阻R1串联于输入晶体管Q1的基极和电流镜110之间。FIG. 4 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention. Referring to FIG. 3 and FIG. 4 , the
具体的，输入阻抗是电路中输入端的等效阻抗，输入阻抗反映了对电流阻碍作用的大小。电阻在电路中对电流起阻碍作用，电阻也是一种阻抗。在电流镜110与输入晶体管Q1的基极间串联第一电阻R1，相当于增加了电路的输入阻抗，从而进行阻抗隔离。Specifically, the input impedance is the equivalent impedance of the input terminal in the circuit, and the input impedance reflects the magnitude of the blocking effect on the current. Resistor acts as a hindrance to the current in the circuit, and resistance is also a kind of impedance. Connecting the first resistor R1 in series between the
或者，阻抗隔离模块210包括：第一电流缓冲器Q3，第一电流缓冲器Q3串联于输入晶体管Q1的基极和电流镜110之间，第一电流缓冲器Q3的偏置端接入第一偏置电压。Alternatively, the
具体的，第一电流缓冲器Q3的源极与漏极间的电压差是可变的，当此电压差增大时所通过的电流会随之减小；当此电压差减小时所通过的电流会随之增大。因此，可以将第一电流缓冲器Q3等效为电阻，通过改变源极与漏极间的电压差从而调节等效电阻的电阻值。Specifically, the voltage difference between the source and the drain of the first current buffer Q3 is variable, and when the voltage difference increases, the passing current will decrease; when the voltage difference decreases, the passing current The current will increase accordingly. Therefore, the first current buffer Q3 can be equivalent to a resistor, and the resistance value of the equivalent resistor can be adjusted by changing the voltage difference between the source and the drain.
本实用新型实施例通过在输入晶体管Q1和电流镜110间设置第一电阻R1或第一电流缓冲器Q3，增大输入晶体管Q1与电流镜110间的阻抗，减少电流镜110中电容和/或阻抗过小对输入晶体管Q1输入级特性的影响。In the embodiment of the present invention, by setting the first resistor R1 or the first current buffer Q3 between the input transistor Q1 and the
图5是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图。参照图5，该输入偏流补偿电路还包括：FIG. 5 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention. Referring to Figure 5, the input bias current compensation circuit also includes:
工作点稳定模块220，工作点稳定模块220串联于补偿晶体管Q2的基极和电流镜110之间；工作点稳定模块220用于稳定输入晶体管Q1和补偿晶体管Q2的直流工作点。The operating
具体地，直流工作点是指晶体管的基极、集电极和发射极之间的电压有设定关系，只有三者之间的电压满足设定关系时，才能够保证晶体管的直流工作点。对于输入晶体管Q1而言，补偿晶体管Q2和电流镜110的设置改变了输入晶体管Q1的集电极和发射极电压，可能在一定程度上影响其直流工作点。本发明实施例通过设置工作点稳定模块，可以调整输入晶体管Q1和补偿晶体管Q2的集电极和发射极的电压，需要确保处在晶体管的安全工作区。Specifically, the DC operating point means that the voltages between the base, collector and emitter of the transistor have a set relationship, and only when the voltages among the three meet the set relationship can the DC operating point of the transistor be guaranteed. For the input transistor Q1, the configuration of the compensation transistor Q2 and the
示例性地，补偿晶体管Q2的集电极电压保持不变，但是补偿晶体管Q2的基极受工作点稳定模块220的控制，从而影响补偿晶体管Q2的发射极电压。由于补偿晶体管Q2的发射极电压即为输入晶体管Q1的集电极电压，输入晶体管Q1的发射极电压为补偿晶体管Q2的基极电压减去补偿晶体管Q2的基极-发射极电压。因此，通过工作点稳定模块220可以调整输入晶体管Q1和补偿晶体管Q2的直流工作点。这样的设置可以提高输入偏流补偿电路的工作稳定性。Exemplarily, the collector voltage of the compensation transistor Q2 remains unchanged, but the base of the compensation transistor Q2 is controlled by the operating
图6是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图。图7是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图。图8是本实用新型实施例提供的又一种输入偏流补偿电路的结构示意图。结合图6、图7及图8，工作点稳定模块220包括：第二电阻R2，第二电阻R2串联于补偿晶体管Q2的基极和电流镜110之间；FIG. 6 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention. FIG. 7 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention. FIG. 8 is a schematic structural diagram of another input bias current compensation circuit provided by an embodiment of the present invention. Referring to FIG. 6 , FIG. 7 and FIG. 8 , the operating
或者，工作点稳定模块220包括：第二电流缓冲器Q4，第二电流缓冲器Q4串联于补偿晶体管Q2的基极和电流镜110之间，第二电流缓冲器Q4的偏置端接入第二偏置电压；Alternatively, the operating
或者，工作点稳定模块220包括：二极管D，二极管D串联于补偿晶体管Q2的基极和电流镜110之间。Alternatively, the operating
本实用新型实施例在补偿晶体管Q2和电流镜110间设置第二电阻R2或第二电流缓冲器Q4或二极管D承担分压作用，进而改变补偿晶体管Q2的基极电压和直流工作点,确保输入晶体管Q1的发射极处于晶体管的安全工作区，提高输入偏流补偿电路的工作稳定性。In the embodiment of the utility model, a second resistor R2 or a second current buffer Q4 or a diode D is set between the compensation transistor Q2 and the
本实用新型实施例还提供了一种示波器，该示波器包括：以上任意实施例提供的输入偏流补偿电路；其中，输入晶体管Q1的基极作为示波器的输入端。本实施例提供的示波器，具有以上任意实施例提供的输入偏流补偿电路的有益效果，在此不再赘述。The embodiment of the present utility model also provides an oscilloscope, which includes: the input bias current compensation circuit provided by any of the above embodiments; wherein, the base of the input transistor Q1 is used as the input terminal of the oscilloscope. The oscilloscope provided in this embodiment has the beneficial effects of the input bias current compensation circuit provided in any of the above embodiments, and will not be repeated here.
应该理解，可以使用上面所示的各种形式的流程，重新排序、增加或删除步骤。例如，本实用新型中记载的各步骤可以并行地执行也可以顺序地执行也可以不同的次序执行，只要能够实现本实用新型的技术方案所期望的结果，本文在此不进行限制。It should be understood that steps may be reordered, added or deleted using the various forms of flow shown above. For example, each step described in the utility model can be executed in parallel or sequentially or in a different order, as long as the desired result of the technical solution of the utility model can be achieved, there is no limitation herein.
上述具体实施方式，并不构成对本实用新型保护范围的限制。本领域技术人员应该明白的是，根据设计要求和其他因素，可以进行各种修改、组合、子组合和替代。任何在本实用新型的精神和原则之内所作的修改、等同替换和改进等，均应包含在本实用新型保护范围之内。The above specific implementation methods do not constitute a limitation to the protection scope of the present utility model. It should be apparent to those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made depending on design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.
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