From KCL to Class D Amplifier - esat.kuleuven.be · Osterrieth, Bernard Paulus, Dimitri Pfeiffer, Louis Philipperon, Louis-Antoine Pirnay, Olivier Poncelet, Aimé Pouahoulabou, Marie-Anne

From KCL to Class D AmplifierFrancis Labrique

Charles TrullemansUCL School of EngineeringLouvain-la Neuve Belgium

CAS Education WorkshopSeattle 2008

2ISCAS 2008Ch. TrullemansF. Labrique (EPL)

CAS in the EPL Bachelor program

Year 11st term

2d term

~ 350 studentsany engineering program

~ 90 studentsmajor or minor program in electricity

Year 2

Year 3

1st term

2d term

1st term

2d term

Physics : mechanics, electricity

ElectromagnetismProject: electricity, material science

Circuit theoryProject: circuits

Applied MathemathicsElectronic circuitsDevice physicsTelecom

Bachelor degree

This talk


Objectives

charge flow

Starting point

Bottom-uplearningprocess

Functional view

∫ΣΔ Class D amplifier

Circuit view

Kirchhoff network



Year 11st term

2d term

Physics : mechanics, electricity

Electromagnetism

Project: electricity, material science

Active learning based program

Lectures+ multidisciplinary problem solving+ projects & team work


1st year , 1st term: basic physics

• Fundamental concepts– charge, current, voltage, fields, energy, power …

I

V

Physics:movingchargein an

electricfield

Circuit:power

to/from any

dipole

A

B

3dl I

3E I

Q

links


From Physics to Circuits

• Device modeling: R, C, L

• Elements constraints I V

R

I V

L

I V

C

ρE

σ

ε

μ

σ

ε

μ

= =

= = =

= = =

2

2

1212

G

C C

L L

G g V R IdVC g I C W C Vdt

dIL g V L W L Idt

Underlying physics

Functional model

Just in time: a little touch of Coulomb, Gauss, Biot-Savart, Faraday …

Electromagnetism course to follow, 2d term

links


• Circuit theory– Network constraints: KCL, KVL

– Voltage and current sources

– Equivalent dipoles

• Focusing on 1st order dynamic circuits

From Physics to Circuits

VS

VCR1

R2 C

Circuit theory course to follow, 2d year

ReqVC

Veq C


First Order System

• Dynamic behaviour– Energy

Constant at equilibrium

No instantaneous change

Mechanics

– Voltage time derivative ∝ distance to equilibrium

R

CI

VC ( t )

VS

( )1CC C

dVV V

dt τ ∞= −

links

Derivative vector plotsee: Thomas Calculus p. 644 et 645

tt

VC

links

Their Math textbook


What they do

• Pick up a formula or recipe• Use formal calculus• Don’t bother with all those words or schematics• Keep a secure and tight border between different courses and topics

Archimedes, what, what is that fish formula?

Who? Who? What? What? What?

You know, that... Latin business.

Aquarius aquaticus aqualitus.

The Sword and the StoneDisney 1963


1st year , 2d term

• Build a brushless DC motor + driver– Real life context

– Lab equipment

Stator

Rotor

G

S

D

=

Switch

Buehler standard DC motors

to be replaced by brushless motors

Also: flash lamp, loudspeaker, DC-DC converter


What they do

• Hands on – Oscilloscope, waveforms

– Components

– Measurements & errors

• Problem solving– How to reverse

the magnetic flux?

– How to swicth an inductance current?

• Modeling– Schematics ↔ workbench

Abstract model ≠ virtual reality



Year 21st term

2d term Circuit theoryProject: circuits

Coordinated contents and schedules

2 professors + 2 assistants + 1 technician + 7 tutors (last year master students) = 121 hour staff meeting every week

14 groups of 6 students = 846 hours presential time / week : lecture + exercises + lab

Year 1 Physics course

François BaudartOlivier BulteelThierry DarasJonathan DeniesJulien DevosLaurent DevroeyeThibaut LabbéFrancis LabriqueChristophe MouvetStan SobieskiCharles TrullemansChristophe Vloebergh


1st year , 2d term: course+project

• Course– Circuit theory

– Op Amps

– Phasors• Bode diagram

– Fourier (basics)• Wave spectrum

– Laplace (basics)• Functional

modeling

• Project

– Circuit analysis & design

– Simulation

– Experimentation

– Class D amplifier:

a mix of linear and non-linear circuits

Applied maths course to follow, 3d year

Challenging projectfor the studentsfor the staff

a keystone of motivation

links

links

links

links


The way of the future ?

Class D amplifiers

The official product launch of Elite SC-09TX

will take place at the CES in Las Vegas

on January 7-10.Nu-Force Class D Amplifier

Week 1: Introduction

Motivation is a keystone of learning


Starter: 1-pole Op-Amp circuit

• Paper and pencil

Spice

Experiment

Objectives

• Analysis

• Determining components from a specification

Vout

Cint

Rf

Zf

Vin Rint

X


Project core: ΣΔ Schematic

• Mission– What is this ?

– How does it work ?

– Calculate components values according to specs

– Design another PWM modulator

0

R1

7.7

R2

7.7

V1DC = 15V

V2

DC = 15V

VEE

VCC

VEE OUT7

+2

-3 G 1

V+

8V

-4

B/S6B

5U1

LM111

VCC

VEE 0

VCC

R201k

R12

7.7

R11

7.7

0C1

7.7

0

+

-

OUT

U2

OPAMP

A

R3

7.7Vin

FREQ = 7kHzVAMPL = 7

0

B

Input specs: phone signal Output spec: PWM, < 50 kHz


What they do

0

R1

7.7

R2

7.7

V1DC = 15V

V2

DC = 15V

VEE

VCC

VEE OUT 7+2

-3

G1

V+

8V

-4

B/S 6B5U1

LM111

VCC

VEE 0

VCC

R201k

R12

7.7

R11

7.7

0C1

7.7

0

+

-

OUT

U2

OPAMP

A

R3

7.7Vin

FREQ = 7kHzVAMPL = 7

0

B

DC or sin

Time

100us 150us 200us 250us 300usV(PWM)

0V

15V

VB: PWM

Time

100us 150us 200us 250us 300usV(integr)

0V

-1.2V

VA: triangular

Every groupachievesHand calculationSimulationExperiment

Several groupsachieveDesign


Building PWM modulators

Group 11 final report


Week 8: Preliminary report

• Walking in darkness

The output voltage will be a triangular signal. The rising and falling edge will have exactly opposed slopes.

We are looking for a ratio between R1 and R2. If the voltage at the common node is 0, we get:

We also want the current through C1 when VB » 15 to be exactly opposed to the current at the same place when VB = 0. This gives:

1 1 2 20 15 0− = − + =B R RV R I R I

( )1 2 2− = − −R R RI I I

Group 10 preliminary report

Schematic

driven

approach.

Is the purpose

of this circuit

to produce a

symmetric

triangular

wave ??


Just in time teaching ( 1 hour )

1. Find the functional blocks border lines

2. Identify the interface signals

3. Derive the circuit details from the overall structure

Sum

PWM

Signal Integral Hysteresis


Week 13: Final report

• A great light

When the input signal is null, the mean value of the PWM signal must be null too.


The integrator aims at obtaining a mean error voltage from an error current. The steepest slope occurs when the input signal is close to 0.

Sound

reasoning


Week 14: What they do

∫


in:sine wave PWM output

spectrum

0

R1

7.7

R2

7.7

V1DC = 15V

V2

DC = 15V

VEE

VCC

VEE OUT 7+

2

-3

G1

V+

8V

-4

B/S6B

5U1

LM111

VCC

VEE 0

VCC

R201k

R12

7.7

R11

7.7

0C1

7.7

0

+

-

OUT

U2

OPAMP

A

R3

7.7VinFREQ = 7kHz

VAMPL = 7

0

B

Severalgroupsachieve Top-downsystemdescription


Outcomes

• End result– Working amplifiers ( at least 1/group )

– Listening to the beloved mp3 player through the amplifier (wow !)

• Learning experience– Important steps, part of a progressive process

– Long term competences acquired from now on

• Better perception of the real issue– To pass the exam

– To become a designer


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Bosly, Damien Bouvy, Nicolas Charlier, Benoît Clabots, Martin Coenen, Damien Coppens, Numa Couniot, Vincent Cousin, Simon Crelot, Gatien De Bast, Olivier de Caritat de Peruzzis, Guerric de Crombrugghe de

Looringhe, Charles De Groote, Emmanuel De Neyer, Laetitia de Viron, Adeline Decuyper, Philippe Delandmeter, Olivier Descamps, Nathan Devreese, Diego d'Ursel, Christophe Everarts, Thomas François, Rodolphe Gilliot, Simon Godfrind, Gabriel Gorza, Brieuc Grégoire, Denis Grogna, Pierre-Antoine Haddad,

Benoît Herbin, Julien Jomaux, Simon Labbé, Laurent Lamouline, Sébastien Leboutte, Quentin Leirens, Nicolas Lequin, Nicolas Luyckx, Cédric Marchand, Maxime Marion, Pierre Marot, Michael Marrocco, Guillaume Martin, Grégoire Masquelier, Sébastien Matton, Céline Michel, Laurent Michiels, Philippe Michiels, Justin Morel de Westgaver, Muhire Boniface Nteziyaremye Ntwali, Vincent Nuttin, Cédric

Osterrieth, Bernard Paulus, Dimitri Pfeiffer, Louis Philipperon, Louis-Antoine Pirnay, Olivier Poncelet, Aimé Pouahoulabou, Marie-Anne Pungu Mwange, Alexandre Saint, Alessandro Sarich, Pierre-Yves Sévar, Pierre Slinckx, Cédric Snauwaert, Alexandre Thissen, Nicolas Van den Berge, Eric van den Hove, Pierre-

Hugues Van houte, Aymeric Van Outryve d'Ydewalle, Nicolas Vansnick, Thomas Vansnick, Daniel Vergeylen, Bertrand Vosse, Abdullah Yogurtcu

Thanks


Traditional CAS education The way of the future ?

A question

Documents

From KCL to Class D Amplifier - esat.kuleuven.be · Osterrieth, Bernard Paulus, Dimitri Pfeiffer, Louis Philipperon, Louis-Antoine Pirnay, Olivier Poncelet, Aimé Pouahoulabou, Marie-Anne