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Power supplies are the basic components that provide the correct voltage and current required for the operation of electronic devices. The voltage and current required for electronic devices often vary, so power supplies must provide output voltage and current that can be adjusted to suit different devices.

In this project, a list of components required to make a power supply is given. These components include a voltage regulator, several diodes, several resistors, several polarized capacitors, several potentiometers, and a switch that provides the 12 volts DC output voltage necessary for the operation of many electronic devices.

The power supply design begins in the first step with the use of a rectifier circuit to convert from an AC power supply to a DC power supply. The diodes (D1-D9) used in this circuit convert alternating current (AC) to direct current (DC). At this stage, the use of a filter is necessary, since the output voltage has not yet been regulated.

For filtering, a polymeric electrolytic capacitor was used, using capacitors C1 and C2. These capacitors are used to clear the DC output voltage from unwanted noise and ripples.

Then, the output voltage is fixed using the voltage regulator (U1). A voltage regulator named V_REG_317SINK was used for this project. This voltage regulator uses a potentiometer (R4) to adjust the output voltage to the desired value.

The potentiometer allows the output voltage to be adjusted to the desired value. The R4 and R5 potentiometers are used to fine-tune the output voltage of the regulator. Thanks to these settings, the output voltage can be adjusted precisely to the desired value.

Several resistors (R1, R2, R3, R6, and R7) are used to control the operation of the circuit. These resistors are used to properly direct voltage and current.

A power supply is an electronic circuit that provides the electrical power required for the operation of electrical devices. This circuit is designed to convert AC voltage to correct voltage, and this correct voltage is the power supply required by electronic devices.

This power supply circuit consists of many different components. These include polarized capacitors, diodes, transistors, resistors, and a voltage regulator. Capacitors are used to reduce the noise generated during the operation of the circuit and to provide a smooth DC power to the voltage regulator. Diodes are used to convert AC voltage to correct voltage, while transistors and resistors are used to ensure the stability of the power supply circuit.

The voltage regulator used in the power supply circuit fixes the output voltage at a certain value. In this way, fluctuations in the output voltage are minimized and electronic devices operate more safely.

The power supply circuit can be used in many different electronic devices. For example, many different devices, such as computers, televisions, sound systems, and smartphones, have power supply circuits.

A rectifier circuit is used in the power supply circuit to convert AC input to DC output. In this circuit, C1 and C2 are polarized capacitors. C1 has a capacity of 2200uF and has a voltage resistance of 75V, while C2 has a capacity of 10uF and a voltage resistance of 75V.

Other components from D1 to D9 are 1N5408 and D8 1N5400 series diodes and are used in the rectification circuit. These diodes pass AC signals in the right direction but not in the opposite direction. Thus, the AC input is converted to a DC signal.

Q1 in the power supply circuit is a TIP127 type PNP transistor and is used in the regulator circuit. R4 and R5 are resistors in the regulator circuit with 2.5kohm, 1W bi-level 16mm potentiometers.

A voltage regulator named U1 V_REG_317SINK is used in the regulator circuit. This circuit stabilizes the output voltage at the desired level. R6 are 100 ohm, R7 10k ohm, 1W resistors and they are connected to various parts of the circuit.

The S1 is a 320-938 toggle switch that turns the power supply on and off. J1, J2 and J3 are 3.5mm terminal blocks and are used to interconnect various components in the power supply circuit.

Finally, KK1 is a model SK104-PAD heat sink produced by the Fischer manufacturer and is used in the power supply circuit.

Handcrafted power supplies are often made by those with an interest in electronics. Such sources usually use a transformer as the primary power source and then a rectifier circuit and a voltage regulator to produce the correct voltage and current.

This power supply circuit includes a bridge rectifier to convert the AC (alternating current) input to direct current (DC), and then a voltage regulator to adjust the voltage. Also, there are a number of diodes and resistors in the circuit, these are important for the correct operation of the circuit.

The power supply consists of many different components. These components include electrolytic capacitors, diodes, resistors, transistors, switches, terminal blocks, potentiometers, and LEDs.

This particular power supply circuit includes a TIP127 transistor, a V_REG_317SINK voltage regulator, an SK104-PAD heat sink, a set of 1N5408 diodes, and a set of terminals, resistors, and capacitors. There is also a set of power connections and a switch with a 3.5mm terminal block.

This power supply circuit is ideal for meeting low power requirements for electrical appliances. Moreover, such handmade power supplies can also be used for learning purposes.

The working principle of the power supply can be summarized as follows:

AC input: The power supply takes AC input voltage, which voltage is usually assumed to be 220V AC.

Input filter: AC voltage is first passed through an emi filter through the input filter. This reduces the high frequency noise at the input voltage.

Rectification: Next, the rectifier bridge is activated and the AC voltage is converted to DC voltage. The rectifier bridge contains four diodes, designated D1, D2, D3, and D4.

Smoothing: The fluctuating DC voltage at the rectifier bridge output is smoothed using a large electrolytic capacitor (C1). This reduces unwanted fluctuations in the source output.

Regulator: The voltage regulator (U1) is used to keep the output voltage at a constant level. This reduces fluctuations in the output voltage. The U1 integrated circuit uses a potentiometer (R4 and R5) to adjust the output voltage.

Protection: The power supply also includes several diodes (D5, D6, D7, D8, and D9) and a thermal interrupter (F1) to protect the device in case of overcurrent or overheating.

Output: The power supply output is via a 3.5mm terminal block (J1, J2 and J3). These terminals are used to connect the output voltage to the device.

When these components are combined, users can get an output voltage between 5V and 15V from this power supply.

Another important type of power supply is switching power supplies. Such power supplies offer advantages such as high efficiency, low size and weight, low heat generation and wide input voltage ranges. Switching power supplies use a switch to convert AC voltage to DC voltage. The switch is quickly opened and closed, enabling the DC voltage to be converted into a high frequency AC signal. This high frequency AC signal is then converted into a low voltage DC power supply through a transformer and rectifier circuits.

Another popular type of power supply is linear power supplies. Linear power supplies convert DC voltage directly through a resistor between high current and low current into a low voltage DC power supply. Linear power supplies offer advantages such as low noise levels, low harmonic distortion, high accuracy and stable output voltage. However, such power supplies are often limited by low efficiency, high heat generation, and limited input voltage ranges.

Finally, switched-mode linear power supplies combine the advantages of both switching and linear power supplies. Such power supplies provide high efficiency, low size and weight, wide input voltage ranges, and low noise levels like linear power supplies, low harmonic distortion and stable output voltage, such as switch-mode power supplies.

Power supplies are a critical component to meet the power requirements of electronic devices. Different types of power supplies offer advantages and disadvantages suitable for different applications. Therefore, when choosing power supplies, it is important to consider the needs and features specific to a particular application.

Depending on the correct output voltage achieved, power supplies can generally be classified as low power supplies (e.g. mobile phone chargers), medium power supplies (e.g. household appliances and computers) and high power supplies (e.g. industrial use and power stations)..

In addition, power supplies can be classified as AC input, AC output, AC input DC output, and DC input DC output. AC input AC output power supplies convert the input signal from an AC source into an AC signal and output it. AC input DC output power supplies, on the other hand, convert the input signal from an AC source to direct current (DC) and output it. DC input and DC output power supplies, on the other hand, convert the input signal received from the DC source into a DC signal and output it.

Power supplies may also have a regulated or non-regulated (constant) output voltage. Regulated power supplies have an adjustable mechanism to change the output voltage within a certain range. Unregulated power supplies have a fixed output voltage and this voltage cannot be changed.

Finally, power supplies can operate using different technologies. There are different types of power supplies, such as linear regulators and switching power supplies.

Besides the output voltage and current you want to achieve, other characteristics of the power supply are also important. Some of these are those:

Regulation: It is the stability of the output voltage obtained from the power source. Despite load changes or input voltage changes, the output voltage remains the same.

Efficiency: It is about how much of the energy in the power supply is transmitted to the output and how much is lost. A higher efficiency generates less heat and consumes less energy.

Power factor: It is related to the phase angle of the voltage and current drawn from the power source. A low power factor causes the power supply to run inefficiently and consume more energy.

Ripple: It is the fluctuations and noise coming from the power supply. A high ripple can cause unwanted fluctuations in output.

Protection features: If the power supply is overloaded or short-circuited, it must take safety measures to protect itself and the connected devices.

Size and weight: The size and weight of the power supply may vary depending on the intended use and application area. For example, a household power supply may be portable, while an industrial power supply may be larger and heavier.

Cooling: The power supply gets hot during operation. Therefore, it is important to use a suitable cooling system (fan, thermal paste, etc.).

All of these features affect the performance and functionality of a power supply. When choosing a power supply, it is important to consider the features suitable for a particular application.

Of course, the electrical energy from the alternating current (AC) source is converted into a direct current (DC) source using various circuit elements. This conversion process is performed by a device called an AC-DC power supply. This device is used in most electronic devices in our homes, industrial appliances and even vehicles.

AC-DC power supplies can be made using different technologies. Among them, the most common are:

Linear Power Supplies: These types of power supplies are generally used for low power requirements. The AC voltage is directly reduced by means of a transformer and an array of transistors and diodes are used to regulate the direct current. Linear power supplies provide low noise and high accuracy, but generally have low efficiency.

Switch Mode Power Supplies: These types of power supplies provide high efficiency and are used in many different applications. The AC input is converted to direct current using a switching transistor and a high frequency transformer. Switch-mode power supplies may have higher noise, but are generally preferred because of their higher efficiency and smaller size.

Inverters: Inverters convert DC source to AC source. Such power sources are often used to harness energy from renewable energy sources such as solar panels and wind turbines. Inverters use different technologies to change the waveform of the AC output.

Power supplies come with many different features and parameters. These include features such as output voltage, output current, efficiency, noise, accuracy, regulation, power factor, and protection features. Choosing a suitable power supply is important for correct operation and reliability.”

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