The real fun of modern electronics starts with semiconductors and digital electronics. Electronics is all about signals (in the form of voltages or currents) and processing signals through components and circuits. Semiconductor electronics is achieved by processing electronic signals into binary values (0 and 1, or low and high). This application of semiconductor electronics to process signals as binary values led to the implementation of Boolean logic in the form of digital electronics. Since then, electronic technology has been applied to computer technology. Soon, engineers and researchers devised methods to measure various physical quantities by converting them into analog electrical signals and digitizing those analog signals into digital values. They also devised methods to convert digital signals into equivalent analog electrical signals. Now, computers can also interact and react to the physical world.
Most modern electronics is about "electronic computing" and its application in the real world. The combination of electronic computing with display technology and input/output electronics led to the development of general-purpose computers. The combination of electronic computing and various communication technologies has led to the development of telecommunications, television and Internet technologies. The combination of electronic computing with wireless communication and sensors has promoted the development of mobile electronics and wearable devices. The combination of electronic computing with sensors and actuators has led to the development of applications such as embedded systems, robotics and automation.
But before we embark on our never-ending journey into semiconductors and digital electronics, it's good to have some basic understanding of power supplies. It is the power source that gives life to any electronic circuit or device. Every electronic circuit or device basically needs to have a power supply section or may need to be connected as a load with an external power supply circuit.
The source of electricity can be power transmission lines (mains), electromechanical systems (alternators and generators), solar energy, or storage devices like batteries and batteries. A power source is a power converter that converts power from a source to voltage, current, and frequency suitable for the load circuit. The power source can be alternating current or direct current. Like generators and power supplies, electricity provides AC power, while batteries and solar devices source DC power. The power circuit can input power from AC or DC power, and convert the output AC or DC power into power suitable for the load. Therefore, power circuits can be divided into AC-to-AC, AC-to-DC, DC-to-DC, and DC-to-AC power supplies.
Various AC-to-AC power sources include variable AC power supplies, isolation transformers, and frequency converters. AC to DC power is the most common. Some AC and DC power supplies include astable linear DC power supplies, linear regulated DC power supplies (benchtop power supplies), switching regulated power supplies, and ripple regulated power supplies. Battery-based power sources, solar power sources, and dc-dc converters are all examples of dc-dc power sources. Battery power and solar power are used to power electronic circuits directly, while DC-DC converters are generally used to convert incoming DC power to different levels to power different circuits in the same device, rather than using different AC-DC power sources Get different voltage/current levels. Inverters, generators, and UPSs are commonly used DC-AC power sources.
Variable AC Power
A variable AC power source uses a transformer or an adjustable autotransformer. These are used to convert AC voltage levels. This power supply can be designed using a multi-winding or tapped transformer, or an adjustable autotransformer. These power supplies convert AC voltage and current levels while the frequency of the source power remains the same.
Inverter
Used to convert the frequency of AC power. These can be designed using electromechanical devices such as motor generator sets or with the help of rectifier-inverter sets. The rectifier first converts the AC to DC and then the inverter converts the DC to AC at different frequencies.
isolation transformer
Isolation transformers are used for AC to AC power and require isolation impedance matching between the power supply and the load circuit. Isolation transformers generally do not convert supply voltage levels or frequencies. These circuits are useful when connecting balanced and unbalanced circuits.
These isolation transformers are used to step up or step down voltages while keeping the power supply and output circuits isolated with CE certified reinforced insulation. (Image: Signal Transformer)
non-regulated linearity
Power Unregulated linear power supplies are simple AC and DC power supplies. These designs use step-down transformers, rectifiers, filter capacitors, and discharge resistors. First, a transformer converts the line voltage to the desired voltage level in alternating current. The stepped-down AC voltage is then converted to a DC voltage using a half-wave or full-wave rectifier. The rectifier adopts a diode structure. The pulsating DC from the rectifier is smoothed using filter capacitors. A discharge resistor can be connected in parallel with the filter capacitor for protection.
The unregulated power supply is simple and durable. However, their output voltage may vary due to changes in input voltage or load current. So, none of these are very reliable. Also, these can only be designed to output a fixed voltage and current.
Linear Regulated Power Supply
Linear regulated power supplies are AC and DC power supplies. These are the same unregulated (brute force) power supplies, except they use a transistor circuit operating in the active or linear region instead of a discharge resistor. This active transistor stage can output different precise DC voltage levels. There are several voltage regulator ICs available with integrated active transistor circuits. The linear regulated power supply is stable, safe, reliable and noise-free. There are voltage regulator ICs available for a wide range of input and output voltages and output a fixed DC voltage. The main disadvantages of these supplies are cost, size and energy efficiency. These supplies lose a significant amount of energy due to power dissipation and may need to be regulated with the use of integrated circuit heat sinks.
Switching regulated power supply
A switching regulated power supply is a complex AC and DC power supply that often combines the advantages of unregulated and regulated power supplies. In a switching power supply, the line voltage is rectified into a DC voltage, and then converted into a square-wave AC voltage with the help of a switching tube. This high frequency square wave is then dropped or stepped up and then rectified again. The rectified DC voltage is filtered and then supplied to the load.
Linear power supplies are 10 times larger than similar switching power supplies (below), but linear power supplies have beneficial properties that switching power supplies cannot match.
Switching regulated power supply A switching regulated power supply is a complex AC and DC power supply that often combines the advantages of unregulated and regulated power supplies. In a switching power supply, the line voltage is rectified into a DC voltage, and then converted into a square-wave AC voltage with the help of a switching tube. This high frequency square wave then goes down
drop or step up, then rectify again. The rectified DC voltage is filtered and then supplied to the load.
Ripple regulated power supply
Ripple regulated power supply is an improvement on non-steady AC and DC power supply. It is designed by combining an astable power supply with a transistor circuit operating in the saturation region. The transistor circuit transfers the DC power to the capacitor to maintain the voltage level. The main advantage of a ripple regulated power supply is its energy efficiency.
Adjustable Regulated Power Linear Regulated
Power Supplies can be improved to provide an adjustable voltage range using variable resistors at the ends. This variable resistor reduces the output voltage to an adjustable value. This adjustable power supply can provide a maximum voltage range from zero to power regulation. Symmetric linear regulated power supplies can also be retrofitted to negative voltages.
Batteries and Solar Power
Provide batteries, batteries, solar panels provide DC power. Power from storage devices or solar panels needs to be filtered first to remove pulsating ripples. It can then be regulated to the desired DC voltage level using a voltage regulator integrated circuit. If you need to boost the supply voltage from a battery or solar panel, you can use a transistor as an amplifier.
DC-DC Converter
Used to step up or step down DC voltages. Dc-dc converters can be semiconductor, electromechanical or electrochemical converters. Switching power supplies such as push-pull converters, buck converters, boost converters, and buck-boost converters are typical examples of semiconductor dc-dc converters. These power supplies are typically used to convert DC power (corrected from mains or other AC sources) to provide different DC levels, rather than using many AC-to-DC power supplies in one device.
An example of a 2w DC-DC power supply
DC-AC power supply
These types of power supplies are generally used for power backup. Inverters, UPSs and generators are examples of such power systems.
The most commonly used by electronics hobbyists and engineers are linear regulated power supplies and battery power supplies. Other types of power supplies are generally designed and produced for specific applications or circuits. Some circuits may require the use of a solar panel design power supply.
For starters, it is very convenient to use a linear regulated power supply, which can provide commonly used DC voltages such as 12v, 9V, 5V and 3v. For portable circuits, the same voltage can be achieved by using a battery-based regulated power supply. Battery-based regulated power supplies may require periodic battery replacement. Therefore, linear regulated power supplies that provide commonly used DC voltage levels are the best for prototyping and testing electronic circuits. Production circuits can be powered by batteries or solar panel-based circuits if desired.
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Mr. Bai Jilong has been engaged in the electronics industry for 15 years. He has developed more than 100 products so far, and most of them have been mass-produced.
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It took 5 years since 2018 to record thousands of practical-level electronic engineer series courses, from components to core modules to complete products
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Lao Bai's original intention is "May the world's engineers not take detours" Among them, there are courses explaining MOS tubes and IGBTs in detail