# Regulated Linear Power Supply

## Presentation on theme: "Regulated Linear Power Supply"— Presentation transcript:

Regulated Linear Power Supply

Dual-Output Adjustable Linear Regulated Power Supply

Block Diagram

Simple Description Transformer: “Downconvert” the AC line voltage to a smaller peak voltage Vm, usually about 2-3 Volts larger than the ultimately desired DC output. Diode Rectifier Circuit: produce a waveform with large DC component. Filter: smooth out the rectified sinusoid. Regulator: eliminate residual ripple

c03f34 Half-Wave Rectifier Tin
Cause of ripple: the capacitor is discharged for almost an entire period.

c03f36 inversion Ripple Reduction: Do not allow the capacitor to discharge so frequently

An Inverting Half-Wave Rectifier
If Vin >0, D1 and D2 are off. If Vin <0, D1 and D2 are on and Vout>0.

An Non-Inverting Half-Wave Rectifier
If Vin >0, D1 and D2 are on, Vout>0. If Vin <0, D1 and D2 are off.

Full-Wave Rectifier Inverting Non-Inverting

Full-Wave Rectifier Alternative Drawing
Full-Wave A.K.A. Bridge Rectifier Non-Inverting Inverting

Using Constant Voltage Diode Model
Vout=-Vin-2VD, on Vout=Vin-2VD, on

Input versus Output |Vin|<2VD,on

Modification of Ripple Estimation Formula
Turn-on voltage 1/2 to account for inversion of negative peaks.

Maximum Reverse Voltage
VB=VD,on Vp is the amplitude of Vin VA=VP VAB=VP-VD,on Maximum reverse voltage is approximately Vp

Compare Maximum Reverse Bias Voltage to Half-Wave Rectifier
A reverse diode voltage must sustain larger reverse bias voltage

Currents as a function of time

Application of Bridge Rectifier

Summary

A Voltage Regulator Circuit

Schematic

Full-Wave Rectifier Alternative Drawing
Full-Wave A.K.A. Bridge Rectifier Non-Inverting Inverting

Rectified Waveform

Smoothing Capacitor

LM317/LM337

9.36 V and V

Each capacitor is 100 uF. Resistor is 37.5 Ohms

Increase capacitor from 100
uF to 470 uF. Reduced ripples

Extra Slides

I-V Characteristic of LED