125 Watt Switch Mode Power Supply (SMPS)


Description & Features

Technical Documents

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This 125 Watt Switch Mode Power Supply (SMPS) provides +28 Volts at 4.0 Amps for audio power amplifiers, along with +12.0 Volts and 5.0 Volts for system functions.

This SMPS supplies a small, low cost solution for applications such as wireless speakers, Personal Computer peripheral speakers, and micro component systems.

This power supply is designed to operate from a power line voltage of 85 vac to 264 vac without jumpers or switches. It is compatible with power line frequencies of 50 Hz to 60 Hz. It can also be turned on with a low current, low voltage switch contact. It also provides a high efficiency, “always on” power of +12 Volts at 1 Amp.

In addition to providing +28 Volts at 4.0 Amps, it also has outputs for +5.0 Volts at 300 mA and +12.0 Volts at 1.0 Amps.

The 28 Volt supply is designed to support a surge current of up to 20.0 Amps to accommodate the crest factors encountered in audio reproduction. The noise and ripple are consistent with the requirements for audio amplifier systems.

This power supply is compatible with the Power Supply Volume Control (PSVC) PWM signal from the TAS55xx modulators. This feature allows the 28 Volt supply to vary from 7 Volts to 28 Volts under control of the TAS55xx modulator. PSVC is used for the control of amplifier volume by lowering the power supply voltage. This feature improves the sound quality and system efficiency.

Because of its being a switch mode power supply, it is light weight and generates less heat than a similar solution designed with a linear power supply topology.

  • +28V
  • 4A
  • 50Hz-60Hz
  • Operation from 110V to 220V
  • Additional +12V and +5V rails

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Part Number Status Topology  

125 Watt Switch Mode Power Supply (SMPS)

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Technical Documents
Design files (2)
Title Abstract Type Size (KB) Date
PDF 121 10 Feb 2009
PDF 33 10 Feb 2009

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