My dazzling wall by NUR BAYA MOHD HASHIM

Chapter 4 Oscillator (Lesson 1-3)

baya — 2020-04-19 10:29:36 UTC

Please share whatever knowledge that you understand for Chapter 4 (Lesson 1-3). You can summarize and share here in padlet.

Summarize

2020-04-19 14:36:35 UTC

- : Oscillators are circuits that
produce a repetitive signal on its output.
- Oscillators does not need an input external source to operate.
- The basic component of an oscillator is the op-amp and the positive feedback network.

2020-04-19 14:42:25 UTC

Nurul aimee izzaty bt mohd nizam
191020959

Lesson 1 (basic concept)
-oscillator is a circuit that produce continuous signal on its output from only dc voltage as an inpit
There are 3 type of oscillator
1.feedback
2.crystal
3.relexation
Lesson 2 (basic principal)
-about positive feedback, which is the key feedback for oscillator to work
Lesson 3 (design crateria)
-requirement for oscillator to start up
1. |BA| = 1
2. Total phase shift must be 0° or 360°
- if BA<1 = output fade out
- if BA>1 = output cilpping

2020-04-19 14:45:33 UTC

~Sharveni Ramesh~ <191023027>
From lesson 1 - 3, I can summarized the
i) Definition of oscillator
ii) Types of oscillators
-: feedback oscillator (limited to 1MHz or less & positive feedback)
= wien - bridge
= phase shift
-: crystal oscillator (limited above 1MHz)
= series - resonant
= parallel - resonant
-: relaxation oscillator
= triangular wave
= square wave
= sawtooth wave
iii) Keypoint of oscillation operation : positive f/b
iv) Basic component of oscillator
: op-amp
: positive feedback
v) Basic requirement
: total phase shift = 0 degree or 360 degree.
: BA = 1 ~ barkhausen criterion => constant amplitude
vi) BA < 1 -> oscillation fades out
vii) BA > 1 -> oscillation saturates & cutoff clipping
viii) Build up state to start up the oscillation
= the voltage gain around the positive f/b must be greater than 1.

AISYAH NAZIRAH RAZALI (191020865) lesson 1-3

2020-04-19 15:14:06 UTC

-osscillators are circuits that produces a repetitive signal on output with only dc supply voltage
-oscillator have 3 types which are:
1. feedback oscillator (wien bridge and phase shift)
2. crystal oscillator (series and parallel resonant)
3. relaxation oscillator (triangular, square and saw tooth wave)
- positive feedback is the key to oscillator operation
-basic component : op-amp and positive feedback network
-requirement for oscillator to start up:
1.total phase shift must be 0 or 360 degree
2.loop gain, BA is unity or slightly bigger
-if BA <1, fade out
-if BA>1, cut off clipping

Ahmad Syazwan Bin Ahmad Izham

izham_syazwan49 — 2020-04-19 16:05:25 UTC

191022292

- Oscillator is a circuit that produce a repetitive signal on output with only a dc voltage as the input.

- There are 3 type oscillator:
1- Oscillator with RC feedback circuit (Feedback Oscillator)
Type : Wien-bridge Oscillator, Phase-Shift Oscillator
2- Oscillator with LC feedback circuit (Crystal Oscillator)
Type : Series-Resonant Crystal Oscillator, Parallel-Resonant Crystal Oscillator
3- Relaxation Oscillator
Type : Triangular Wave Oscillator, Square-Wave Oscillator, Sawtooth Oscillator

Oscillator with RC feedback circuit (Feedback Oscillator)
- The Key to Oscillator Operation is positive feedback.
- The component is Op-amp and Positive Feedback network

The requirement :
- Total phase shift must be 0 or 360,
- |BA| = 1 or slightly (Barkhaussen criterion)

If Barkhaussen criterion :
- |BA| < 1 : oscillation will fade out within a few cycles.
- |BA| > 1 : Oscillation may drive itself into saturation and cutoff clip.

Umi Maryam binti Abdul Razak 161022955

2020-04-19 16:12:14 UTC

-Oscillator is a circuit that produce repetitive signal as the output output with a dc voltage as the input and no any external sources.
-Positive feedback is when a portion of the output voltage is fed back again to the input with no net phase shift.
-Types of oscillator :
1) Crystal
2) Relaxation
3) Feedback
-Basic requirement for oscillator to operate is:
1) |BA| = 1 or slightly larger
2) Phase shift = 0/360
-When |BA| < 1, output fade out
-When |BA| > 1, output cutoff clipping

2020-04-19 16:15:35 UTC

Nur Aini Anis binti Daud 191020946
1. Oscillator is a circuit that produce repeatitive signal without needing an external input.
2. 3 type of oscillator
-oscillator with RC feedback
-oscillator with LC feedback
-relaxation oscillator
3. Require positive feedback
4. Design criteria
-total phase shift must be 0 degree or 360 degree
-BA = 1 or slightly larger
-Barkhaussen criterion, BA = 1
5. BA < 1 , oscillation fade out
6.BA > 1 , oscillation saturation or cutoff clipping.

Lee Jessie 191020905

2020-04-19 16:20:16 UTC

Definition : Oscillators are circuits that produces a repetitive signal on output with only dc supply voltage
3 types of oscillator
- Oscillator with RC feedback circuit (Feedback Oscillator)
- Oscillator with LC feedback circuit (Crystal Oscillator)
- Relaxation Oscillator

Positive feedback (key to operate)
Requirement for oscillator to start up:
1.Total phase shift must be 0 or 360 degree
2.loop gain, BA =1 or slightly bigger
BA<1 = output fade out
BA>1 = output clipping

tengku nur izzati bt tengku deraman 191023305

2020-04-19 16:26:42 UTC

Lesson 1:

-oscillator produces repetitive signal on its output from only a dc voltage as the input

3 types of oscillator:

-Feedback oscillator
- Crystal Oscillators
- Relaxation Oscillator

Lesson 2:

Feedback Oscillator Principles: positive feedback is the key to oscillator operation

Lesson 3:

Basic requirement for oscillator:

1. Total phase shift,φ of the loop gain must be 0 or 360 degrees

2. |βA| equal to unity or slightly larger at the desired oscillation frequency Barkhaussen criterion,
|βA| =1

- if BA<1 = output fade out
- if BA>1 = output cilpping

Pavithrah Sanmugasuntaram-191023026

2020-04-19 16:43:49 UTC

Definition: oscillator produces repetitive signal on its output from only a dc voltage as the input.

3 Types of oscillator:

1) Feedback Oscillator.
- Wien- bridge oscillator
-Phase-shift oscillator
2) Crystal Oscillator.
-Oscillator with LC feedback circuit
3) Relaxation Oscillator.
-Triangular Wave
-Square-Wave
-Sawtooth Wave

Basic requirement for oscillator:
1) Total phase shiftf the loop gain must be 0 or 360 degree.
2) |βA| equal to unity or |βA| =1
βA<1 = Oscillation fades out.
βA>1 = Oscillation becomes saturated and cutoff clipping.

Ho Kai Jun 191020894

2020-04-19 16:53:32 UTC

1)RC circuit- circuit which
resistor and capacitor being connected.
2)LC circuit-circuit which inductor and capacitor being connected.
3)In lead-lag network, the phase'-shift across the network lags with increasing frequency and leads with decreasing frequency. It gives 0 phase shift and 1/3 attenuation at resonant frequency.
4)In lead network, a resistor and a capacitor are connected in series.
5)In lag network, resistor and capacitor are connected parallely.
6)To start oscillation in steady state,the voltage gain around the positive feedback loop must be greater than 1.

Intan Nuraisha binti Rosdi 191020898

intannuraisha — 2020-04-19 17:14:39 UTC

Choo Kuok Fong 191022293

2020-04-19 18:36:48 UTC

- Oscillators are circuits that
produce a repetitive signal on its output.
- Oscillators does not need an input external source to operate.
- The basic component of an oscillator is the op-amp and the positive feedback network.

- There are 3 type of oscillator
1.Feedback oscillator ( RC component in the circuit)
2.Crystal oscillator ( LC component in the circuit)
3.Relexation oscillator (generate non-sinusoidal signal)

- Requirement for oscillator to start up:
1.Total phase shift must be 0° or 360°
2.BA =1 or slightly bigger. （Barkhaussen Criterion)

FATIN NAZIRAH BINTI ANUAR (171081311)

2020-04-19 18:46:51 UTC

DEFINITION :-
- Oscillators are circuits that produces a repetitive signal or continuous signal on its output from only a DC voltage as the input.

-It does't need any external source to become input.

-Oscillators itself will become an input for the amplifier.

Application: Communication systems,digital systems(including computers),test equipment.

3 Types of oscillator :

a) Feedback oscillator
1.limited to 1MHz or less positive feedback
- > Wien-bridge
-> Phase shift

b) Crystal oscillator
1.Limited above 1MHz

c) Relaxation oscillator
1.Triangular wave
2.Square wave
3.Sawtooth wave

Basic component of an oscillator
1. Op-amp
2. positive feedback

Basic requirement
1. Total shift =0 degree or 360 degree
2. BA = 1~ barkhausen

Criterion for oscillator to fullfill:
1. BA < 1 =Oscillation will fade out within a few cycles
2. BA > 1 = Oscillation may drive itself into saturation and cutoff clipping.

Build-up state of steady state oscillations
-To start oscillate.....the voltage gain must be greater than 1!

NURNAJWA FATINI BINTI MUHAMMAD NASRUL (161020860)

2020-04-19 18:47:28 UTC

Definition: Oscillators are circuits that produce a repetitive signal on its output from only a dc voltage as the input.

Types of oscillator:

1) Feedback Oscillator

2) Crystal Oscillator
3) Relaxation Oscillator

-Feedback oscillator relies on the positive feedback of the output to maintain oscillation.

-Design criteria for oscillators
1) Total phase shift of the loop gain must be 0 or 360.
2) |BA| equal to unity slightly larger at the desired oscillation frequency.

-When BA>1, oscillation may drive itself into saturation and cutoff clipping.
-When BA<1, the output fades out.

Muhd Asyraff Bin Marzuki 161020848

2020-04-19 20:32:30 UTC

What I learn so far is that There are many types of oscillator for example
feedback oscillator , crystal oscillator , relaxation oscillator

What is an oscillator?
An electronic oscillator is an electronic circuit that produces a periodic, oscillating electronic signal, often a sine wave or a square wave. Oscillators convert direct current from a power supply to an alternating current signal.

Oscillator will only oscillate when two conditions is met that are phase shift must be 0' or 360' and the magnitude of loop gain must be unity

when 𝛃A >1 cutoff clipping and saturation meanwhile when 𝛃A < 1 the oscillator output fade out

AMEER AZIZI BIN ZULKARNAIN 191020868

theameerazizi — 2020-04-20 02:55:29 UTC

OSCILLATORS
A circuits producing repetitive signal on output using dc supply voltage.

Feedback Oscillator (RC)
Relaxation Oscillator
Crystal Oscillator (LC)

Components:
OP amp & positive feedback.

Requirement:
|BA| = 1 or slightly larger
Phase shift = 0/360

Condition:
|BA| < 1, output fade out
|BA| > 1, output cutoff clipping

MAHIRAH NABILAH BINTI SHAMSUL BAHAR (191022998)

2020-04-20 06:00:59 UTC

-Oscillators are circuits that

produce a repetitive signal on its output

from only a dc voltage as the input

-There are 3 type of oscillator
1.Feedback oscillator ( RC component in the circuit)
2.Crystal oscillator ( LC component in the circuit)
3.Relexation oscillator (generate non-sinusoidal signal)
--Design criteria for oscillators
1) Total phase shift of the loop gain must be 0 or 360.
2) |BA| equal to unity slightly larger at the desired oscillation frequency.
- if BA<1 = output fade out or damping
- if BA>1 = output saturated and cutoff cilpping