{"id":20731,"date":"2025-03-07T10:58:49","date_gmt":"2025-03-07T02:58:49","guid":{"rendered":"https:\/\/www.wbyq.cn\/?p=20731"},"modified":"2025-04-22T16:06:39","modified_gmt":"2025-04-22T08:06:39","slug":"%e6%99%ae%e8%b5%9b%e6%96%af%e6%95%b0%e5%ad%97%e6%ba%90%e8%a1%a8%e5%bf%ab%e9%80%9f%e3%80%81%e5%87%86%e7%a1%ae%e8%bf%9b%e8%a1%8c%e4%b8%89%e6%9e%81%e7%ae%a1bjt%e7%89%b9%e6%80%a7%e5%88%86%e6%9e%90","status":"publish","type":"post","link":"https:\/\/ad.wbyq.cn\/en\/20731","title":{"rendered":"Purcells Digital Source Meter for Fast, Accurate Triode (BJT) Characterization"},"content":{"rendered":"
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Triode (BJT) Characterization<\/p>\n\n\n\n

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Specialized in semiconductor electrical testing<\/p>\n<\/div><\/div>\n\n\n\n

         Triode is one of the basic semiconductor components, with current amplification, is the core component of electronic circuits. Triode is a semiconductor substrate on the production of two very close to each other PN junction, the two PN junction of the semiconductor is divided into three parts of the entire block, the middle part of the base area, the two sides of the part of the emitter and collector area.<\/p>\n\n\n

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        Parameters that are often of interest in designing circuits are current amplification factor \u03b2, inter-pole reverse currents ICBO, ICEO, maximum permissible collector current ICM, reverse breakdown voltages VEBO, VCBO, VCEO, and parameters such as the input-output characteristic curves of the triode.<\/p>\n\n\n\n

Input\/Output Characteristics <\/strong><\/p>\n\n\n\n

        Triode characteristic curve is a curve reflecting the relationship between the voltage and current of each electrode of the triode, and it is used to describe the working characteristics of the triode, and the commonly used characteristic curves are input characteristic curve and output characteristic curve: Input characteristic curve indicates the relationship curve between input current (i.e., the base current IB) and input voltage (i.e., the voltage between the base pole and the emitter VBE) when the voltage between the E-pole and the C-pole VCE stays unchanged. When VCE=0, it is equivalent to a short circuit between the collector and emitter, i.e., the emitter junction is connected in parallel with the collector junction. Therefore, the input characteristic curve is similar to the volt-ampere characteristic of PN junction, which is exponential. When VCE increases, the curve will be shifted to the right. For low power transistors, one input characteristic curve with VCE greater than 1V can approximate all input characteristic curves with VCE greater than 1V.<\/p>\n\n\n

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Triode Input Characteristic Curve<\/p>\n\n\n\n

        The output characteristic curve shows the relationship between the output voltage VCE and the output current IC of the triode when the base current IB is certain. According to the output characteristic curve, the working state of the triode is divided into three areas. Cutoff area: It includes a set of working curves with IB=0 and IB\u30080 (i.e. IB is opposite to the original direction). When IB = 0, IC = Iceo (called penetration current), which is very small at room temperature. In this region, the two PN junctions of the transistor are reverse biased, even if the VCE voltage is high, the current Ic in the tube is very small, and the tube is equivalent to a switch in the open circuit state. Saturation region: the value of the voltage VCE in this region is very small, VBE>VCE, and the collector current IC increases quickly with the increase of VCE. At this time, the two PN junctions of the triode are in forward bias, the collector junction loses the ability to collect electrons in a certain area, and the IC is no longer controlled by the IB.VCE has a great effect on the control of the IC, and the tube is equivalent to the on state of a switch. Amplification area: In this area, the emitter junction of the transistor is forward biased and the collector is reverse biased. When VEC exceeds a certain voltage, the curve is basically flat, this is because when the collector voltage increases, most of the current flowing into the base electrode is pulled away by the collector, so when VCE continues to increase, the change of current IC is very small, in addition, when IB changes, IC changes proportionally, that is to say, IC is under the control of IB, and the change of IC is much larger than the change of IB, and \u25b3IC and \u25b3IB are directly proportional to each other. In other words, IC is controlled by IB, and IC changes much more than IB, and \u25b3IC and \u25b3IB are proportional to each other, and there is a linear relationship between the two, which is why this region is also called the linear region. In an amplifier circuit, a triode must be used in the amplifier region.<\/p>\n\n\n

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Triode Output Characteristic Curve<\/p>\n\n\n\n

        According to different materials and applications, the voltage and current of transistor devices are also different technical parameters, for transistor devices below 1A, we recommend 2 sets of S-series source meters to build a test program, with a maximum voltage of 300V, a maximum current of 1A, and a minimum current of 100pA, which can satisfy the needs of low-power MOSFET testing.<\/p>\n\n\n

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        For MOSFET power devices with maximum currents of 1A~10A, it is recommended to set up a test program with two P-series pulse source meters with a maximum voltage of 300V and a maximum current of 10A.<\/p>\n\n\n

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        For MOSFET power devices with a maximum current of 10A~100A, we recommend the P series pulse source meter + HCP to build a test program with a maximum current of up to 100A and a minimum current as low as 100pA.<\/p>\n\n\n

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Inter-pole reverse current<\/strong><\/p>\n\n\n\n

<\/strong>        ICBO refers to the reverse leakage current flowing through the collector junction when the emitter of the triode is open-circuited; IEBO refers to the current from the emitter to the base when the collector is open-circuited, and it is recommended to use a Purcell S-series or P-series source meter during the test.<\/p>\n\n\n

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Reverse breakdown voltage <\/strong><\/p>\n\n\n\n

        VEBO is the reverse breakdown voltage between the emitter and base when the collector is open-circuit; VCBO is the reverse breakdown voltage between the collector and base when the emitter is open-circuit, which is determined by the avalanche breakdown voltage of the collector junction; VCEO is the reverse breakdown voltage between the collector and emitter when the base is open-circuit, which is determined by the avalanche breakdown voltage of the collector junction; VCEO is the reverse breakdown voltage between the collector and emitter when the base is open-circuit. VCEO is the reverse breakdown voltage between the collector and emitter stages when the base is open, which is determined by the avalanche breakdown voltage of the collector junction. When testing, it is necessary to select the appropriate instrument according to the technical parameters of the device breakdown voltage. For the breakdown voltage below 300V, it is recommended to use the S series benchtop source meter or P series pulse source meter with a maximum voltage of 300V, and for the devices with a breakdown voltage above 300V, it is recommended to use the E series with a maximum voltage of 3500V.<\/p>\n\n\n

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CV Characteristics<\/strong><\/p>\n\n\n\n

    Like MOS tubes, triodes are characterized by CV measurements.<\/p>\n\n\n\n

[Test operation instructions]<\/strong><\/p>\n\n\n\n