Logic Circuit - Short essay

In computer engineering, logic circuit or logic family may refer to one of two related concepts.  A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply characteristics within a family. Many logic families were produced as individual components, each containing one or a few related basic logical functions, which could be used as "building-blocks" to create systems  or as so-called "glue" to interconnect more complex integrated circuits.

The list of packaged building-block logic families can be divided into categories, listed here in roughly chronological order of introduction, along with their usual abbreviations:

1. Resistor–transistor logic (RTL)
   1.1 Direct-coupled transistor logic (DCTL)
   1.2 Resistor–capacitor–transistor logic (RCTL)

2. Diode–transistor logic (DTL)
   2.1 Complemented transistor diode logic (CTDL)
   2.2 High-threshold logic (HTL)

3. Emitter-coupled logic (ECL)
   3.1 Positive emitter-coupled logic (PECL)
   3.2 Low-voltage positive emitter-coupled logic (LVPECL)
   3.3 Complementary transistor micrologic (CTuL)

4. Gunning transceiver logic (GTL)

5. Transistor–transistor logic (TTL)

6. P-type metal–oxide–semiconductor logic (PMOS)

7. N-type metal–oxide–semiconductor logic (NMOS)
   7.1 Depletion-load NMOS logic
   7.2 High-density nMOS (HMOS)

8. Complementary metal–oxide–semiconductor logic  (CMOS)

9. Bipolar complementary metal–oxide–semiconductor logic (BiCMOS)

10. Integrated injection logic (I²L)

Vibration Resistance - Short essay

Vibration Resistance also know as vibration proofing, is an ability of a device to protect against vibration. Many equipments have high requirements on the physical environment of work, and their performance is susceptible to vibration or even malfunctions and malfunctions. Solid state relays have better vibration resistance than mechanical relays.

Corrosion Resistance - Short essay

The ability of metallic materials to resist the corrosive effects of surrounding media is known as corrosion resistance. Solid state relays have better corrosion resistance than mechanical relays.

Mildew Resistance - Short essay

The Mildew Resistance or mold-proof product has the ability to inhibit the growth of mold spores and the growth of mycelium.Solid state relays have better Mildew Resistance than mechanical relays.

Contact Wear - Short essay

Contact Wear is the mechanical wear of the mechanical relays' contacts.

Electrical Level - Short essay

Electrical Level or logic voltage levels. In logic circuits, two voltages are commonly used to represent two logic states, but sometimes two currents are used to represent them. High and low thresholds are specified for each logic circuit. When below the low threshold, the signal is "low". When above the high threshold, the signal is "high". Intermediate levels are undefined, resulting in highly implementation-specific circuit behavior.

Contact Bounce - Short essay

Contact Bounce, or contact chatter,contact jitter usually occurs at the contacts of mechanical relays. When the mechanical contacts are connected or disconnected, due to the elastic action of the mechanical contacts, the mechanical relays will not be turned on steadily when connected, nor will be turned off imitately when disconnected. Therefore, there is a series of jitters at the moment of connecting or disconnecting, ans this phenomenon is contact jitter.

Switching Speed - Short essay

Switching speed or switching rate, is the switching  frequency of the mechanical relays and the solid state relays. The higher the switching frequency (or the shorter the switching time), the faster the switching speed.

Mechanical Failure - Short essay

Mechanical failure refers to a significant reduction in the performance of the equipment and is below the minimum required by normal requirements, and is no longer able to maintain normal operation, due to mechanical wear, spark,electric arc,contact jitter and etc. Equipment failures generally include:
   (1) Destructive failures that cause the equipment system to lose functionality immediately.
   (2) Performance failures associated with degrading device system performance.

Mechanical Wear - Short essay

Mechanical wear refers to the friction between the friction surfaces that are in contact with each other to produce relative motion, which will produce the frictional resistance of the movement of the tissue, causing the consumption of mechanical energy and conversion to release heat, causing mechanical wear.

Electro-Magnetic Compatibility - Short essay

Electromagnetic compatibility (EMC) is the branch of electrical engineering concerned with the unintentional generation, propagation and reception of electromagnetic energy which may cause unwanted effects such as electromagnetic interference (EMI), radio frequency interference (RFI) or even physical damage in operational equipment. The goal of EMC is the correct operation of different equipment in a common electromagnetic environment.

Electro-Magnetic Interference - Short essay

Electromagnetic interference (EMI), also called Radio-frequency interference (RFI), is an interference caused by Electromagnetic Radiationgenerated by an interference source to cause malfunction of an electronic device. The electromagnetic interference can cause abnormal operation of the circuit and even directly damage the device.
Types of electromagnetic interference: EMI can be divided into several categories according to the source and signal characteristics. The origin of interference, often called "noise" in this context, can be man-made (artificial) or natural. 

Radio Frequency Interference - Short essay

Radio-frequency interference (RFI), also called Electromagnetic interference (EMI) when in the radio frequency spectrum, is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction. The disturbance may degrade the performance of the circuit or even stop it from functioning. In the case of a data path, these effects can range from an increase in error rate to a total loss of the data.

Transistor - Short essay

 A transistor, or triode is a electronic component used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually as discrete Components, but many more are found embedded in integrated circuits.

According to the structure, the transistor can be divided into: BJT, SCR, TRIAC, MOSFET, IGBT, and etc.

According to the electrical polarity (positive and negative), the transistor can be divided into: n–p–n, p–n–p (BJTs); n-channel, p-channel (FETs).