5v 1a power supply using lm2575


Posted on Feb 7, 2014

A Power Transistor which is having a drop of 4 Volts across it and passing 3 amps thru it, may dissipate around 12 Watts of Heat, This is the problem in Series Regulators. While a Saturated Transistor or Mosfet with 1 Volts across and 3 Amps Thru will be just 3 Watts. But then a fully on transistor or mosfet cannot be controlled or regulated, for


5v 1a power supply using lm2575
Click here to download the full size of the above Circuit.

that we turn it ON and OFF very fast so that the right amount of current or voltage is delivered. The way this is done is PWM - Pulse Width Modulation. In this the mosfet or transistor is switched ON-OFF at say 100 kHz, but the ON duration is varied to control the output. The longer the duration of ON time more energy or punch is transferred. Switching losses will be present depending on how fast the rise and fall times of the pulses are. The Pulsed AC or Chopped DC can be smoothed to the Average with Inductors and Capacitors. The reactive pulses of the Inductor has to be absorbed by a Schottky Rectifier 1N5817 - 20V-1A fast switching diode with low switching losses.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    DC servo motor driver with MC33030
    Automatic Gain Control ( AGC )
    Build a Crystal Shortwave Radio
    12V to 5V 3A DC converter step down Regulator
    10 watt rf amplifier for 18mhz by
    FlasherCircuit using NE 555 IC for Lamp
    LM2002 Series 8W audio power amplifier circuit
    Pressure Transmitter Data Acquisition System circuit 1B31,18 bit A / D converter AD1170 and MCS-51 microcontroller



    Top