Electronic components are components of electronic components and small machines and instruments. Electronic components include resistors, capacitors, potentiometer, electron tubes, radiator, electromechanical components, connectors, semiconductor discrete devices, electronic devices, laser device, electronic display devices, optoelectronic devices, sensors, power supply, switch, micro motors, electronic transformers, relays, printed circuit board, integrated circuits, various types of circuit, piezoelectric crystals, quartz, ceramic magnetic materials, printed circuit substrate base board, special material and electronic glue process of electronic functions (with) products, electronic chemical materials and components, etc.


Resistor. It is a current limiting element. When the resistance is connected to the circuit, the resistance value of the resistor is fixed, usually two pins.Fixed resistors are those whose resistances cannot be changed. Resistance variable is called potentiometer or variable resistor. The ideal resistor is linear, that is, the instantaneous current through the resistor is proportional to the applied instantaneous voltage. 

Variable resistor for partial pressure. On the exposed resistor body, one or two movable metal contacts are pressed tightly. The contact position determines the resistance between any end of the resistance body and the contact. The type of domestic resistor consists of four parts (not applicable to sensitive resistance)

Part one: the main name, expressed in letters, represents the name of the product.Like R is for resistance, W is for potentiometer.

Part two: The material indicated by the letter indicates the material used for human body strength, T carbon film, H synthetic carbon film, S organic solid, N inorganic solid, J-metal film, nitride film Y, film deposited in C, glass glazing Film I, X ray film.

Part three: classification, generally expressed by Numbers, individual types by letters, indicating the type of products.1-normal, 2-normal, 3-uhf, 4-high resistance, 5-high temperature, 6-precision, 7-precision, 8-high pressure, 9-special, g-high power, t-adjustable.

Part four: serial number, represented by Numbers, represents different types of products of the same kind, so as to distinguish the external dimensions and performance indicators of the products, such as: R T 1 type common carbon film resistance.



Capacitance is one of the most widely used electronic components in electronic equipment. It is widely used in isolation, coupling, bypass, filtering, tuning circuit, energy conversion and control circuit.Is expressed in C capacitance, capacitance ferrari (F), micro farads (uF), leather ferrari (pF), 1 F = 10 uF = 10 ^ 6 ^ 12 pF

The models of capacitors are generally composed of four parts (not suitable for pressure-sensitive, variable and vacuum capacitors). In turn, they represent names, materials, categories, and serial Numbers.

Part one: name, in alphabetical form, capacitor C.

Part two: materials, expressed in letters.

Part three: classification, generally expressed in Numbers, individual letters.

Part four: serial Numbers, represented by Numbers. With letters product material: A tantalum electrolysis, B - such as polystyrene nonpolar high frequency ceramic film, C -, D - electrolytic aluminium electrolysis, E - the other materials, G - alloy electrolytic, H - composite medium, I - glass glaze, J - metallized paper, L - polyester and other polar organic film, N - niobium electrolytic, O - glass membrane, Q - film, T - low frequency ceramics, V - mica paper, mica, Z - Y paper


Inductor coil

The inductor coil is wound round and round the insulated pipe by wires, which can be hollow or contain iron core or magnetic powder core, or inductor.Is expressed with L, Henry (H), Henry (mH), Henry (uH), 1 H = 10 ^ 3 mH = 10 ^ 6 uH.

The classification of inductance by inductance form classification: fixed inductance, variable inductance. According to the nature of magnetic conduction: hollow coil, ferrite coil, iron core coil, copper core coil.By nature of work: antenna coil, oscillating coil, choke coil, trap coil, deflection coil.According to the structure of winding: single-layer coil, multi-layer coil, honeycomb coil.

Main characteristic parameters of inductor coil

1. The inductance L indicates the inherent characteristics of the coil itself, which is independent of the current size. In addition to the special inductor coil (color code inductor), the inductor quantity is generally not specially marked on the coil, but marked by a specific name.

2. XL inductor coil's resistance to ac current is called XL, and the unit is ohm. The relation between it and inductance L and ac frequency f is XL=2 stores fL

3. quality factor Q quality factor Q is said coil quality of a physical quantity, Q is the ratio of inductance XL instead of the equivalent resistance, i.e., Q = XL/R coil, the high Q value the less losses in the loop. The Q value of the coil is related to the dc resistance of the wire, the dielectric loss of the frame, the loss caused by the shield or iron core, and the influence of high frequency skin effect. The Q value of the coil is usually between tens and hundreds.

4. The capacitance between the turns and turns of the distributed capacitor coil, between the coil and the shield, between the coil and the bottom plate is called distributed capacitance. The existence of distributed capacitance makes the Q value of the coil decrease and the stability of the coil decrease, so the smaller the distribution capacitance of the coil is, the better.

inductor coil

Semiconductor devices

Semiconductor device model named method semiconductor device model consists of five parts (field effect devices, semiconductor, PIN type tube, special devices, the type of laser device named only the third part, four, five). The meanings of the five parts are as follows:

Part one: digital representation of the number of effective electrodes of semiconductor devices.

Part two: using Chinese pinyin letters to represent the materials and polarity of semiconductor devices. Represents diode: a-n germanium material, b-p germanium material, c-n silicon material, d-p silicon material. Represents triode: a-pnp germanium material, b-npn germanium material, c-pnp silicon material, d-npn silicon material.

Part three: using Chinese pinyin letters to represent the internal type of semiconductor devices.P - the common tube, V - microwave tube, W - regulator tube, pipe, Z - C - parameters rectifier tube, L - rectifier stack, S - tunnel pipe, N - damping, U - photoelectric device, K - switch tube, small X-ray low-frequency power tube (F < 3 MHZ, Pc < 1 W), G - high frequency low power tube (F > 3 MHZ, Pc < 1 W), D - low frequency high power tube (F < 3 MHZ, Pc > 1 W), A - high frequency high power tube(f > 3 MHZ, Pc > 1 w), T - semiconductor thyristor (controlled rectifier), Y - bulk effect device, B - avalanche pipe, J - step recovery, CS - field effect tube, BT - half body special devices, FH - pipe, PIN - type PIN tube, JG - laser device.

Part four: number five: the Chinese pinyin alphabet for specification number for example: 3DG18 for NPN silicon material high frequency triode.

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