Basic Principles of Sinusoidal Oscillators
Linear oscillator
 Linear region of circuit : linear oscillation
 Nonlinear region of circuit : amplitudes stabilization
Barkhausen criterion
XS



Xf
Amplifier A
XO
Frequency-selective
network 
 loop
gain L(s) = β (s)A(s)
 characteristic equation 1-L(s) = 0
 oscillation criterion L(j0= A(j0) β(j0) = 1
Prof. Tai-Haur Kuo
12 - 1
Electronics(3), 2012
Basic Principles of Sinusoidal Oscillators (Cont.)
at 0, the phase of the loop should be zero and the
magnitude of the loop gain should be unity.
Oscillation frequency 0 is determined solely by
φ
∆ω0 
∆φ
dφ dω
∆φ
0
ω0
ω
A steep phase response results in a small 0 for a
given change in phase 
Prof. Tai-Haur Kuo
12 - 2
Electronics(3), 2012
Nonlinear Amplitude Control
To sustain oscillation : βA>1
a.overdesign for βA variations
b.oscillation will grow in amplitude
 poles are in the right half of the s-plane
c.Nonlinear network reduces βA to 1 when the desired
amplitude is reached
 poles will be pulled to j-axis
Prof. Tai-Haur Kuo
12 - 3
Electronics(3), 2012
Nonlinear Amplitude Control (Cont.)
Limiter circuit for amplitude control
 linear region
VO  (
Rf
)Vi
R1
R3
R2
VA  V
 VO
R2  R3
R2  R3
R4
R5
VB   V
 VO
R4  R5
R4  R5
V
R2
D1
VI
A
Rf
R1
R3


VO
R4
D2
B
R5
-V
Prof. Tai-Haur Kuo
12 - 4
Electronics(3), 2012
Nonlinear Amplitude Control (Cont.)
 nonlinear
region
R2  R3
R3
 VD )
(V
R2
R2  R3
R3
R3
 V
 VD (1 )
R2
R2
R
R
similarly, L   V 4  VD (1 4 )
R5
R5
VO
VA  -VD  L  
Slope  
VO
L
(R f R 4 )
R1
0
VI
Slope  
L
Slope  
Prof. Tai-Haur Kuo
12 - 5
Rf
R1
(R f R 3 )
R1
Electronics(3), 2012
OPAMP-RC Oscillator Circuits
Wien-bridge oscillator
 R  Zp
Ls   1 2 
 R1  Zp  Z s
R
1 2
R1

1
3  SCR 
SCR
R
1 2
R1
L jω  
1 

3  j ωRC 

ωRC


R2
R1
_
VO

C
Vd
C
1
     For phase  0. ω0RC 
ω0RC
R
ZS
R
ZP
1
RC
R
     Ls   1  2  2
R1
 ω0 
Prof. Tai-Haur Kuo
12 - 6
Electronics(3), 2012
OPAMP-RC Oscillator Circuits (Cont.)
Wien-bridge oscillator with a limiter
 15V
R 3  3k
D1
a
20.3k
R 4  1k
10k
V1
_
VO

10k
16nF
16nF
10k
D2
R 5  1k
b
R 6  3k
 15V
Prof. Tai-Haur Kuo
12 - 7
Electronics(3), 2012
OPAMP-RC Oscillator Circuits (Cont.)
vO
50k
10k
b
a
p
-

16nF
10k
16nF
Prof. Tai-Haur Kuo
10k
12 - 8
Electronics(3), 2012
Phase-Shift Oscillator
Without amplitude stabilization
C
C
C
-K
R
R
R
------- phase shift of the RC network is 180 degrees.
Total phase shift around the loop is 0 or 360
degrees.
Prof. Tai-Haur Kuo
12 - 9
Electronics(3), 2012
Phase-Shift Oscillator (Cont.)
With amplitude stabilization
50k
100k
P1
Rt
D1
16nF
x
C
16nF
C
R 10k
16nF
_
V
R1
R2
vO

C
R 10k
D2
R3
R4
V
Prof. Tai-Haur Kuo
12 - 10
Electronics(3), 2012
Quadrature Oscillator
V-
R1
R2
R3
R4
C
2R
V
2R
VO2
_
OP2
X
R

_
OP
 1
Prof. Tai-Haur Kuo
2R
VO1 C
12 - 11
Rf
(Nominally 2R)
Electronics(3), 2012
Quadrature Oscillator (Cont.)
-------Break the loop at X, loop gain L(s) =
1
oscillation frequency 0 
RC
V02
1
=
VX S2C2R 2
-------Vo2 is the integral of Vo1
90° phase difference between Vo1 and Vo2
“quadrature” oscillator
Prof. Tai-Haur Kuo
12 - 12
Electronics(3), 2012
Active-Filter Tuned Oscillator
Block diagram
V2
V
-V
f0
t
V
 High-distortion v2
 High-Q bandpass
t
V2
-V
Prof. Tai-Haur Kuo
V1
V1
 low-distortion v1
12 - 13
Electronics(3), 2012
Active-Filter Tuned Oscillator (Cont.)
Practical implementation
QR
C
R
R
R
R

C
V2
Prof. Tai-Haur Kuo
-
R1
V1
12 - 14
Electronics(3), 2012
A General Form of LC-Tuned Oscillator
Configuration
Many oscillator circuits fall into a general form shown
below
RO
3
1
V̂13

-
RO
2
A

I 0

Z2

V13

VO
VO
Z3
V13
2
Z1

Z3
1
- A v Vˆ 13
Z2

V13

3
Z1
ZL
ZL
Z1,Z2,Z3 ：capacitive or inductive
Prof. Tai-Haur Kuo
12 - 15
Electronics(3), 2012
A General Form of LC-Tuned Oscillator
Configuration (Cont.)
 AvVˆ13 Z L
VO 
Z L  RO
 Av Z1Z 2
V
Z1
VO T  13 
V13 
Z1  Z 3
Vˆ13 RO ( Z1  Z 2  Z 3 )  Z 2 ( Z1  Z 3 )
if Z1  jX 1, Z 2  jX 2 , Z 3  jX 3
1
for capacitanc e
X  L for inductance X  
C
Av X 1 X 2
T
jRO ( X 1  X 2  X 3 )  X 2 ( X 1  X 3 )
for oscillation, T  10
 X1  X 2  X 3  0
 Av X 1
Av X 1 X 2
T 

 X 2 ( X1  X 3 ) X1  X 3
AX
T  v 1
X2
Prof. Tai-Haur Kuo
12 - 16
Electronics(3), 2012
A General Form of LC-Tuned Oscillator
Configuration (Cont.)
With oscillation
|T| = 1 and T = 0, 360, 720, … degree.
1
(X = ωL or X = )
ωC
i.e. T = 1
 X1 & X2 must have the same sign if Av is positive
 X1 & X2 are L, X3 = -(X1 + X2) is C
or X1 & X2 are C, X3 = -(X1 + X2) is L
Transistor oscillators
1.Collpitts oscillator
-- X1 & X2 are Cs, X3 is L
2.Hartley oscillator
-- X1 & X2 are Ls, X3 is C
Prof. Tai-Haur Kuo
12 - 17
Electronics(3), 2012
LC Tuned Oscillators
Two commonly used configurations
 1.Collpitts (feedback is achieved by using a capacitive
divider)
 2.Harley (feedback is achieved by using an inductive
divider)
 Configuration
1.Collpitts
2.Hartley
R
R
C1
L1
C
L
a.c. ground(VDD )
Prof. Tai-Haur Kuo
C2
a.c. ground(VDD )
12 - 18
L2
Electronics(3), 2012
LC Tuned Oscillators (Cont.)
Collpitts oscillator
 Equivalent circuit
sC 2 Vπ
sC 2 Vπ
C2
L
VO  Vπ (1  s 2LC 2 )
C

Vπ

GmVπ
R
C1
R
= loss of inductor + load resistance of oscillator +
output resistance of transistor
Prof. Tai-Haur Kuo
12 - 19
Electronics(3), 2012
LC Tuned Oscillators (Cont.)
1
+SC1)(1+S2LC2 )V=0
R
1
3
2 LC 2
S LC1C2 +S (
)+S(C1+C2 )+(gm + )=0
R
R
1 w 2LC2
(gm + 
)+j  W(C1+C2 )  W 3LC1C2  =0
R
R
SC2 V+gmv+(
S=jw
 For
oscillations to start, both the real and imaginary
parts must be zero
 Oscillation
ω0 =
Prof. Tai-Haur Kuo
frequency
1
c1c 2
L(
)
c1 + c 2
12 - 20
Electronics(3), 2012
LC Tuned Oscillators (Cont.)
 Gain
c2
c2
gmR  (Actually, gmR  )
c1
c1
 Oscillation
amplitude
1.LC tuned oscillators are known as self – limiting
oscillators. (As oscillations grown in amplitude,
transistor gain is reduced below its small – signal
value)
2.Output voltage signal will be a sinusoid of high
purity because of the filtering action of the LC tuned
circuit
Hartley oscillator can be similarity analyzed
Prof. Tai-Haur Kuo
12 - 21
Electronics(3), 2012
Crystal oscillators
Symbol of crystal
Circuit model of crystal
L
CS
CP
r
Prof. Tai-Haur Kuo
12 - 22
Electronics(3), 2012
Crystal oscillators (Cont.)
Reactance of a crystal assuming r = 0
 1 

s  
LCS 
1


sCP s2  CP  CS 
(Crystal is high – Q device)
LCSCP
2
1
Z(s) 
sCP 
1
sL 
1
sCS
1
 2

ω
 S LC
S

Let 
ω2  1  1  1 
 P L  CS CP 

1  ω2  ωS2 
 2

 Z jω   j
2 
ωCP  ω  ωP 
Crystal
reactance
inductive
0
ωS
ω
capacitive
If CP  CS , then ωP  ωS
Prof. Tai-Haur Kuo
ωp
12 - 23
Electronics(3), 2012
Crystal oscillators (Cont.)
The crystal reactance is inductive over the narrow
frequency band between ws and wp
Collpitts crystal oscillator
 Configuration
R
C1
crystal
a.c. ground(VDD )
Prof. Tai-Haur Kuo
12 - 24
C2
Electronics(3), 2012
Crystal oscillators (Cont.)
 Equivalent
CP
circuit
L
CS <<CP , C1, C2
1
 ω0 
=ωS
LCS

C2
vπ
CS
R
C1
-
Prof. Tai-Haur Kuo
12 - 25
Electronics(3), 2012
Crystal oscillators (Cont.)
-22V
L
61~122uH
C gd +C stray
1MHz
XTAL
Prof. Tai-Haur Kuo
C
10M
2.2kΩ
C=300pF
D
2N2608
S
L

0.02μF
C
-22V
Bias circuit
(For AC,-22V and
ground are the same=0)
12 - 26
Electronics(3), 2012
Crystal oscillators (Cont.)
A v X1
 Since return ratio T= X
then X1 must be large for
2
the loop gain to be greater than one.
ω closes to ωp and
 X1 is very large when 



ω
ω
ω
P
 S

1
 X 1&X 2 are inductive
ωC
1
j
Z 2 =L//C=
=
1
1
For 1MHz crystal,
 ω C+
jω C+
jω L
ωL
C=300pF
1
1
1
 X2=
 ω>
>0  ωL>
L  84.4μH
1
ωC
LC
 ωC+
1 1
ωL
 1MHz
 X 1+X 2 +X 3 =0 & X 3 = 
2π
Prof. Tai-Haur Kuo
12 - 27
LC
Electronics(3), 2012
Bistable Multivibrators
Multivibrators
(3 types)
bistable：two stable states
monostable：one stable state
astable：no stable state
Bistable
 Has two stable states
 Can be obtained by connecting an amplifier in a
amplifier in a positive-feedback loop having a loop gain
greater than unity. I.e. βA>1 where β=R1/(R1+R2)
Prof. Tai-Haur Kuo
12 - 28
Electronics(3), 2012
Bistable Multivibrators (Cont.)
 Bistable
circuit with clockwise hysteresis
R2
R1
L
v+

-
vI
vo
vO

-
VTL
0
VTH
vI
L-
 Clockwise
hysteresis (or inverting hysteresis)
L+：positive saturation voltage of OPAMP
L- ：negative saturation voltage of OPAMP
Prof. Tai-Haur Kuo
12 - 29
Electronics(3), 2012
Bistable Multivibrators (Cont.)
 VTH
R1
 βL  
L
R1  R 2
R1
 VTL  βL  
L
R1  R 2
– Hysteresis width = VTH - VTL
Prof. Tai-Haur Kuo
12 - 30
Electronics(3), 2012
Noninverting Bistable Circuit
Counterclockwise hysteresis
Configuration
R2
R1
vI

-
v+

-
vo
L
vO
VTL
0
vI
VTH
L-
v + =vI
R2
R1
+v 0
R1+R 2
R1+R 2
For v 0 =L+ , v + =0,vI =v TL  v TL =  L+ (
For v 0 =L- , v + =0,vI =v TH
Prof. Tai-Haur Kuo
R1
)
R2
R1
 v TH =  L  ( )
R2
12 - 31
Electronics(3), 2012
Noninverting Bistable Circuit (Cont.)
Comparator characteristics with hysteresis
 Can reject interference
Signal corrupted
with interference
VTH
VR  0
VTL
t
Multiple
zero crossings
Prof. Tai-Haur Kuo
12 - 32
Electronics(3), 2012
Generation of Square and Triangular Waveforms
using Astable Multivibrators
Can be done by connecting a bistable multivibrator with a
RC circuit in a feedback loop.
v2
L
v1
VTL
VTH  βL 
VTL  βL 
0
L-
t
L
t
L-
C
Prof. Tai-Haur Kuo
VTH
v1
v2
12 - 33
R
Electronics(3), 2012
Generation of Square and Triangular Waveforms
using Astable Multivibrators (Cont.)
v O t 
T1 T2
L
R2
R1
L-
v+


-
R
v-
vO
-
VTH
v - t 
 βL 
0
VTL  βL 
VTH
v  t 
 βL 
0
VTL  βL 
Prof. Tai-Haur Kuo
t
0
12 - 34
To L 
t
To L Time constant
= RC
t
Electronics(3), 2012
Generation of Square and Triangular Waveforms
using Astable Multivibrators (Cont.)
During T1
V  L   L   βL  e

t
τ
where τ  RC, β 
R1
R1  R 2
L 
1  β  
 L 
if V  βL  at t  T1  T1  τ ln
1 β
During T2
V  L   L   βL  e

t
τ
 L 
1  β 
L 

if V  βL  at t  T2  T2  τ ln
1 β
1 β
; L   L  is assumed 
T  T1  T2  2τ ln
1 β
Prof. Tai-Haur Kuo
12 - 35
Electronics(3), 2012
Generation of Triangular Waveforms
V1
t
C
R
v2
L
V1
_
0
VTL

VTH
v1
V2
t
V2
L-
Bistable
V2
L
V1
T1
T2
0
VTH
t
T2
0
VTL
L
T
Prof. Tai-Haur Kuo
T1
Slope 
12 - 36
-L 
RC
t
Slope 
 L
RC
Electronics(3), 2012
Generation of Triangular Waveforms (Cont.)
During T1
1 T1
LL T
VTL  VTH    iCdt   1 ;
C 0
RC
V  VTL
 T1  RC TH
L
where iC 
L
R
During T2
Similarily
VTH  VTL
 T2  RC
L 
To obtain symmetrical waveforms
T1  T2  L    L 
Prof. Tai-Haur Kuo
12 - 37
Electronics(3), 2012
Monostable Multivibrators
Its alternative name is “ one shot “
v E (t)
(βL

V
)
Has one stable state
+
D2
Can be triggered to a quasi-state
R2
E
C2
L
D2
L-
R4
R1
A

_
C1
βL -
v (t)
VD1 B
R3
βL Prof. Tai-Haur Kuo
T
v (t)
βL  
B
D1
v A (t)
12 - 38
To L 
To L 
Electronics(3), 2012
Monostable Multivibrators (Cont.)
During T1
VB (t)  L   (L   VD1 )e

t
R 3 C1
VB (T)  βL   βL   L   (L   VD1 )e

T
R 3 C1
VD1  L 
 T  R 3C1 ln(
)
βL   L 
ForVD1  | L  |  T  R 3C1(
1
)
1 β
βL+ is greater then VD1
Stable state is maintained
Prof. Tai-Haur Kuo
12 - 39
Electronics(3), 2012
Monostable Multivibrators(Cont.)
Monostable multivibrator using NOR gates
 VDD
Vo1
Vin
NOR
vin
V VT
R
vX
VO2
C
VDD  VT
v O1

NOR
VX
v O2
 3 2 VDD
VDD
VDD
VDD
VT  VDD 2
0 T  T1
Prof. Tai-Haur Kuo
t
0
T1
t
12 - 40
0
T1
t
0
T1
Electronics(3), 2012
t
Mono-stable Multivibrator (Cont.)
C
C

-
Vc

VO1  0
-

R
VDD
v C (0)  0
v x  VDD (1  e

t
RC

vX
-
-

Vc
-
VO1  VDD

R
vX
VDD
-
v C (T1 )   VT
v x  VDD  VT e
)
v x (T1)  VT  VDD (1  e

T1
RC

t
RC
)
VDD
 T1  RCln
 RCln2  0.693RC
VDD  VT
where VT 
Prof. Tai-Haur Kuo
VDD
; VT is NOR gate threshold voltage
2
12 - 41
Electronics(3), 2012
Mono-stable Multivibrator (Cont.)
Monostable multivibrator with catching diode
 VDD
Vin
Vo1
NOR
R
Vx
C
5.6V
VX
VO2
NOR
forward resistance of diode
VD
5V
D
Time constant  R f C
Time constant  RC
0
Prof. Tai-Haur Kuo
T1
t
12 - 42
Electronics(3), 2012
Astable Multivibrator Using NOR(or Inverter) Gates
v
V DD
VO1
VX
VO2

( ii) v
o2
:V D D  0
T
1
2 T1
T
1
2 T1
t
V DD
v C_
v
0
t
X
VDD VT
VT 
w h e n t= 0
: 0  VDD
( iii) v x = ( V D D + V T ) e
V DD
2
0
w h e n t= 0
V T
-t
RC
V DD
v
VT
( iv ) v c = v x - V O 2 = - V D D + ( V D D + V T ) e
Prof. Tai-Haur Kuo
o2
C
Transient behavior
(1)0<t<T1
o1
0
v
R
( i) v
o 1
12 - 43
-t
RC
0
V T
T
C
2 T1
t
1
T
1
2 T1
t
Electronics(3), 2012
Astable Multivibrator Using NOR(or Inverter) Gates
(Cont.)
(2)T1<t<(T1+T2)
( i) v o 1 :0  V D D
w h e n t= T 1
( ii) v o 2 :V D D  0
w h e n t= T 1
( iii) v x = V D D - ( V D D + V T ) e

( t- T 1 )
RC
( iv ) v c = v x - V O 2 = v x = V D D - ( V D D + V T ) e
Prof. Tai-Haur Kuo
12 - 44

( t- T 1 )
RC
Electronics(3), 2012
Astable Multivibrator Using NOR(or Inverter) Gates
(Cont.)
Oscillation frequency
v x (T1 )=VT
 (VDD +VT )e
 T1 =RCln

t
RC
=VT
VDD +VT
VT
VDD
, then T1 =RCln3 and T2 =RCln3
2
1
0.455

oscillation frequency f0 =
2RCln3
RC
If VT =
Prof. Tai-Haur Kuo
12 - 45
Electronics(3), 2012
Astable Multivibrator Using NOR(or Inverter) Gates
(Cont.)
 With
catching diode atV X
VO1
VX
VO2
T1  T2  RCln2
R

0
 Asymmetrical
f0 
v C_
C
VDD
square wave
VO1
VX
VDD
2
(ii)R 1  R 2
1
0.721

2RCln2
RC
(i)VT 
R1
D1
VO2
R2
D2

v C_
C
Prof. Tai-Haur Kuo
12 - 46
Electronics(3), 2012
The 555 IC Timer
Widely used as both a monostable and astable
R n Sn
multivibrator
0
0
0
1
Used as monostable multivibrator
1
1
VCC
Threshold R 1
C
V
c
V TH
R1
Trigger VTL
V
t
R1

_
R Q
1
0
N/A
v t (t)
Comparator 1

_
0
1
Q n+1
Q nn
Totem-pole
output stage
v t  V TL
VO
S Q
0
v c (t)
V TH
VCC (1  e  t RC )
 2VCC 3
Comparator 2
Q1
V cc
3
2V cc
V2 
3
2V cc
Vc 
 Rn  1
3
V1 
v
O
0
T1
0
T1
(t)
v(t)
Discharge
Prof. Tai-Haur Kuo
transistor
12 - 47
Electronics(3), 2012
The 555 IC Timer (Cont.)
 T1
t

v x  VCC  VCC  V(0)e RC
 For
 For
0 t
t = T1, v C (T1 )  VTH
 T1  RCln
Prof. Tai-Haur Kuo
(V(0)  VCE(sat)  0)
2VCC

3
VCC  V(0)
 RCln3 (V(0)  0)
VCC
3
12 - 48
Electronics(3), 2012
The 555 IC Timer (Cont.)
Used as an astable multivibrator
VCC
( R A  RB ) C
VCC
555 timer chip
Comparator 1
Threshold R 1
2 Vcc
3
Vcc
VTL =
3
VTH =
0
T1
T2
R
A
t
2V cc
 S  0, R  1
Vc 
3
V
V c  cc  S  1, R  0
3
V cc
2V cc
 Vc 
 S  R0
3
3
R
Vc
VTH
R1
Trigger VTL
B
C
V
t
Prof. Tai-Haur Kuo
R Q
Totem-pole
output stage
VO
S Q

_
R 1 Comparator 2
Q1
T1  R B Cln2 ,T2  T1  (R A  R B )Cln2
Oscillation frequency f 

_
Discharge transistor
1
1

T2 (R A  2RB )Cln2
12 - 49
Electronics(3), 2012
Sine-Wave Shaper
Shape a triangular waveform into a sinusoid
Extensively used in function generators
Note：linear oscillators are not cost-effective for low
v
frequency application
not easy to time over
wide frequency ranges
O
0
vf 0 T
2
T
t
0
T
T
2
t
Prof. Tai-Haur Kuo
12 - 50
Electronics(3), 2012
Sine-Wave Shaper (Cont.)
Nonlinear-amplification method
 For various input values, their corresponding output
values can be calculated
Transfer curve can be obtained and is similar to
 VCC
RC
RC
_ v 
O
(Sine wave)
vi
Q2
Q1
(Triangula r wave)
R
I
I
- VEE
Prof. Tai-Haur Kuo
12 - 51
Electronics(3), 2012
Sine-Wave Shaper (Cont.)
Breakpoint method
 Piecewise linear transfercurve
 Low-valued R is assumed
V1 and V2 are constant
V1  Vin  V1  Vout  Vin
V1  Vin  V2  D2 is on (voltage drop VD )
 V0  V1  VD  (Vin  VD  V1 )
R5
R5  R 4
V2  Vin  D1 is on  limit V0 to V2  VD
Prof. Tai-Haur Kuo
12 - 52
Electronics(3), 2012
Sine-Wave Shaper (Cont.)
V
D1
D2 R
5
In
R4
D3 R 5
D4
out
R1
In
out
 V2
R2
 V1
R3
 V2
R3
 V1
 V1
 V1
R3
 V2
5
1
2
4
0
 V2
3
R1
V
Prof. Tai-Haur Kuo
12 - 53
Electronics(3), 2012
Precision Rectifier Circuits
Precision half-wave rectifier --- “superdiode”
VO
" Superdiode "
Vi

_
VA
1
1
VO
R
An alternate circuit
D2
R1
Vi
Prof. Tai-Haur Kuo
Vi
0
VO
R2
1
_
D1
1
VO

0
12 - 54
Vi
Electronics(3), 2012
Precision Rectifier Circuits (Cont.)
 Application：Measure
AC voltages
R2
C
D2
R4
R1
Vi
_
A1
D1
R3

A2
V1
Average
Prof. Tai-Haur Kuo
V1 
VP R 2
π R1
_

VO
；where Vp is the peak
amplitude of an input
sinusoid
12 - 55
Electronics(3), 2012
Precision Rectifier Circuits (Cont.)
If
1
 ωmin
R 4C
 V2  
Prof. Tai-Haur Kuo
；ωmin is the lowest expected
frequency of the input sine wave
VP R 2 R 4
π R1 R 3
12 - 56
Electronics(3), 2012
Precision Full-Wave Rectifiers
A
DA
A
1
B
DB
RL
or
B
C
Prof. Tai-Haur Kuo
12 - 57
Electronics(3), 2012
Precision Full-Wave Rectifiers (Cont.)
_
Vi
A

A2
C
E
R2
R1
_

Prof. Tai-Haur Kuo
D1
A1
VO
VO
D2
F
P
Vi
RL
12 - 58
Electronics(3), 2012
Peak Rectifier
With load
Super diode

_

vi
-
C
buffered

vO
-
RL
R
D2
_

vi
Prof. Tai-Haur Kuo

A1
D1
C
12 - 59
_
A2


vO
-
Electronics(3), 2012