What are the main parameters of electronic components? What are their respective characteristics? (I)

The main parameters of electronic components:

The main parameters of electronic components include characteristic parameters, specification parameters and quality parameters. These parameters reflect the electrical properties of an electronic component and the conditions for its completion from different angles. They are interrelated and mutually constrained.

What are the characteristic parameters of electronic components?

The characteristic parameters of an electronic component are used to describe the electrical function of an electronic component in a circuit, and can usually be expressed by the name of the component, such as a resistance characteristic, a capacitance characteristic, or a diode characteristic. The volt-ampere characteristic, that is, the relationship between the voltage applied across the component and the current passing through it, is used to express the characteristic parameters of the component. The volt-ampere characteristics of electronic components are mostly straight lines or curves. Under different test conditions, the volt-ampere characteristics can also be a broken line or a cluster of curves.

What are the specifications of electronic components?

The number of characteristic parameters describing electronic components is called their specification parameters. Specifications include nominal values, allowable deviation values and accuracy levels, ratings and limits.

(1) Nominal value: The social demand for electronic equipment is huge, and the types and annual output of electronic components are even greater. However, in the production process, the value of electronic components is inevitably discretized; and the actual circuit requirements for component values are various. In order to facilitate mass production and allow users to select suitable electronic components within a certain range, we have specified a series of values as the standard value of the product, called the nominal value.

(2) Allowable deviation value and accuracy level: The actual production of components, the value of which is impossible to be exactly the same as the nominal value, there will always be a certain deviation. The relative deviation between the actual value and the nominal value is expressed as a percentage, reflecting the precision of the component values. For components with a certain nominal value, the actual values produced in large quantities are normally distributed, and an acceptable range is specified for these actual values, which is the relative deviation; the maximum allowable range is specified, which is called the allowable value. Deviation (referred to as "tolerance"). Different allowable deviations are also referred to as numerical accuracy levels (referred to as "accuracy"), and standard series are specified for the accuracy level, represented by different letters. For example, the allowable deviation of commonly used resistors is ±5%, ±10%, ±20%, and their accuracy levels are indicated by the letters J, K, and M respectively (previously indicated by I, II, and III). The allowable deviation of precision resistors is ±2%, ±1%, ±0.5%, which are denoted by G, F, and D, respectively.

(3) Rated value and limit value: When the electronic components are working, they must be subjected to voltage and current, and consume power. If the voltage is too high, the insulation material of the component will be broken down; if the current is too large, it will cause excessive power consumption and heat, which will cause the components to be burnt. The voltage, current, and power consumed by electronic components are also affected by environmental conditions such as temperature, humidity, and atmospheric pressure. To this end, we specify the rating of electronic components, generally including rated operating voltage, rated operating current, rated power consumption and rated operating temperature. They are defined as the maximum voltage, current, power consumption, and ambient temperature at which an electronic component can operate normally for a long period of time (to complete its specific electrical function).

In addition, the working limit value of the electronic component is also specified, which is generally in the form of a maximum value, which respectively indicates the maximum value of the component, such as the maximum operating voltage, the maximum operating current, and the highest ambient temperature.

(4) Other specifications: In addition to the nominal values, allowable deviation values, rated values, limit values, etc. described above, various electronic components also have their specific specifications. For example, the characteristic frequency fT of the semiconductor device, the cutoff frequency fα, fβ, the open-loop amplification factor K0 of the linear integrated circuit, the fan-out coefficient N0 of the digital integrated circuit, and the like. When selecting electronic components, these parameters should be considered according to the needs of the circuit.