Description: Transformerless power supply FET power supply. Refer to that page for an explanation about the related circuit diagram. It is often required to supply electricity to the consumer at low voltage, specifically 220V. An external adapter can be used, but it is not ideal, and to reduce the size of the device, a power supply must be located within the device. This 5V power supply uses the LM2995 in the converter circuit, which can be connected directly to 220V. To achieve this, AC voltage is converted to DC voltage across the diode bridge VD1 and then lowered to 40V.
The transformerless power supply circuit described utilizes a field-effect transistor (FET) to achieve a compact design while delivering the necessary voltage to power electronic devices. This type of power supply is particularly advantageous in applications where space is limited, as it eliminates the need for bulky transformers.
The circuit operates by connecting directly to a standard 220V AC source. The initial step involves the use of a diode bridge, designated as VD1, which rectifies the incoming AC voltage into pulsating DC. Following this, a smoothing capacitor is typically employed to reduce voltage ripple, providing a more stable DC output.
Once the DC voltage has been rectified, it is essential to regulate this voltage to meet the requirements of the load. In this case, the LM2995 voltage regulator is utilized. This component is designed to step down the voltage from the rectified level (approximately 40V) to a stable 5V output, suitable for powering low-voltage electronic devices. The LM2995 is particularly noted for its efficiency and reliability in providing a consistent output voltage despite variations in input voltage and load conditions.
Additional components such as filtering capacitors and resistors may be included in the design to ensure optimal performance, reduce noise, and enhance the stability of the output voltage. Proper heat dissipation measures should also be considered, as the FET and voltage regulator may generate heat during operation, particularly under heavy load conditions.
Overall, this transformerless power supply circuit presents an effective solution for powering low-voltage devices directly from a high-voltage AC source, streamlining the design and reducing the overall footprint of the electronic device.Transformerless power supply FET power supply. Go to that page to read the explanation about above power supply related circuit diagram. Is often requiredtosupply electricityto theconsumerlowvoltage 220V. Youcanusean externaladapter- butit`s bad, andtoreduce the size ofthe devicerequires apower supplylocate din the device. This 5v power supply used LM2995 to the convertercircuitwhichcan be connected directly to220V. Todo this, ACconvertedto DCvoltageacross the diodebridgeVD1, andthenloweredto40V. Above 40Vwe.
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