Diode Circuits Voltage Regulation Rectifier Circuit Half-Wave Rectifier Tin Cause of ripple: the capacitor is discharged for almost an entire period.

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Transcript Diode Circuits Voltage Regulation Rectifier Circuit Half-Wave Rectifier Tin Cause of ripple: the capacitor is discharged for almost an entire period.

Diode Circuits
Voltage Regulation
Rectifier
Circuit
Half-Wave Rectifier
Tin
Cause of ripple: the capacitor is discharged for almost an entire period.
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
Inverting
Full-Wave A.K.A. Bridge Rectifier
Non-Inverting
Using Constant Voltage
Diode Model
Vout=-Vin-2VD, on
Vout=Vin-2VD, on
Input versus Output
|Vin|<2VD,on
Addition of the Smoothing
Capacitor
Modification of Ripple
Estimation Formula
Modification:
1. Turn-on voltage
2. 1/2 to account for inversion of negative
peaks.
Maximum Reverse Voltage
VB=VD,on
VA=VP
Vp is the amplitude of Vin
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
Application of Limiting
Circuits
Limit the signal amplitude at a suitable point in the receiver
Characteristic of a Limiting
Circuit
A Simple Limiter
General Limiter Circuit
Application of Voltage
Doubler
Electronic systems typically provide a global supply
voltage: 3V
Design of some circuits will be simplified if they from
a higher supply voltage.
Voltage Doubler
Floating Capacitor
Capacitor Divider
Capacitor Diode Circuit
Ideal diode.
Vout pinned to 0 V
Positive charges begin to leave the left
Plate of C1, turning D1 off.
C1 is now a floating capacitor
Generating 0 to 2Vp
Waveform
Peak Detector
Voltage Doubler
0 to 2Vp waveform
Peak Detector
Diode as a Voltage Shifter
Application:
We may need to shift the average level of a signal up
and down because the subsequent stage (e.g. an amplifier)
may not operate properly with the present dc level.
A Simple Level Shift
Shift up the DC by 2 VD, On
A simple electronic switch
CK is 1: I1=1, diodes are shorted, and
Vin=Vout.
CK is 0,diodes are off, charges are stored
across C1.