Electronics Fab Lecture Outline

Electronics Fab Lecture Outline

Joe Paradiso (joep@media.mit.edu; 1 Cambridge Ctr, 5 FL)
Introduction, analogies
Learning to speak French by walking into a cafe and ordering a meal

Objectives:

Feeling for basic analog and digital circuitry

Some discretes, OpAmps, simple logic (TTL/CMOS)

Some handy circuits

Concepts in basic signal conditioning

Little bit of hands-on prototyping

Avoid getting into the most common trouble

"Reflexive" habbits (bypass caps, etc.)

Know some things to look out for when it doesn't work...
No real RF or HF stuff (& associated black arts) covered in this lecture
Handy Books:

Art of Electronics (Horowitz and Hill)

The OpAmp Cookbook (Walter K. Jung)

Active-Filter Cookbook (Don Lancaster)

CMOS Cookbook (Don Lancaster)

TTL Cookbook (Don Lancaster)

The IC Timer Cookbook (Walter K. Jung) [O/P]

Audio IC OpAmp Applications (Walter K. Jung) [O/P]
Magazines:

Circuit Cellar INK

Nuts & Volts, Popular Electronics...

Electronic Design, EDN, NASA Tech Briefs...

Component and corporate resources

Databooks

Web searches (a few out of many vendors)

Personal, info sites, like:

http://www.itl.co.uk/HomePages/PaulReynolds/semi.html

Vendors (some examples)

DigiKey (http://www.digikey.com )

Hosfelt Electronics (great surplus - http://www.hosfelt.com )

JameCo Electronics (surplus/computer stuff - http://www.jameco.com )

Marlin P. Jones (wild-stuff surplus - http://www.mpja.com )

JDR Electronics (in-between - http://www.jdr.com )

Future/Active Electronics (retail & distributor - http://www.future-active.com )

Allied Electronics (http://www.allied.avnet.co )

Newark Electronics (http://www.newark.com )

Radio Shack!! (http://www.radioshack.com )

Basic Quantities; Voltage, current, power, AC/DC

Passive Components:

Thru-Hole and surface-mount

Resistors

Function

Turn current into voltage

Limit current

Combine/Weight signals

Set time constants, damping, etc.

Color code (same order as ribbon cable colors)

(0-9 = black,brown,red,orange,yellow,green,blue,purple,gray,white)

Tolerances (silver = 10%, gold = 5%, red = 2%, brown = 1%)

Power Ratings (1 W, 1/2W, 1/4W, 1/8W)

Ohm's Law I = V/R

Voltage Divider V1 = R1/(R1+R2)

Potentiometer, trimpots

Series ( R = R1 + R2 + R3 +…)

Parallel ( R = 1/(1/R1 + 1/R2 + 1/R3 + …)
Capacitors

Function

Structure, energy in electric field

Impedance [|z| = 1/(2p fC)]; differentiate - pass AC, block DC

How to read them

Types:

Glass, polystyrene, mica, polypropolene,

mylar, ceramic, electrolytic, tantalum, supercap

Some defining characteristics

Voltage capacity

DC leakage

Voltage dependance

Hysteresis (memory)

Series inductance

High frequency performance

Electrolytic ratings, !!polarity!!

Role of bypass capacitors (typically 0.1 uF)

Series circuits (C = 1/(1/C1 + 1/C2 + 1/C3 + …)

Parallel circuits (C = C1 + C2 + C3 + …)

Passive RC filters

Cutoff frequency= 1/(2pRC), 6 dB/octave, 45° phase @ 3 dB
Diodes

Structure (PN), voltage drop, functions

Zeners

Peak Detector circuits

Bridge (full-wave) rectifiers

LED's
Inductors

Structure, energy in magnetic field

Low Frequency usage not very common...

Series and Parallel math like resistors:

Series: L = L1 + L2 + L3 + …)

Parallel: L = 1/(1/L1 + 1/L2 + 1/L3 + …)

Impedance (|z| = f L/2p); integrates - tends to pass DC, block AC

Filters (analogous to RC, but now highpass…)

Resonators

Parallel LC; z goes to infinity at f = 1/(2p sqrt(LC)); bandpass

Series LC; z goes to zero at f = 1/(2p sqrt(LC)); notch, pumping
The transformer

Vsec = (Nsec/Npri) Vpri

Step up (Nsec > Npri)

Step down (Npri > Nsec)

Impedance conversion ( Z-eff[pri] = (Npri/Nsec)² Zsec )

Isolation

Integrated Circuits (IC's)

OpAmps

Ideal model

Comparitors

Hysteresis

Follower/Buffer

Non-inverting w. gain

Inverting amplifier

Transresistance (C-V)

Summer

Clamping with diode

Differential amplifier and instrumentation amplifier

Differentiator, High Pass active filter

Integrator, Low Pass active filter

Single supply operation - biasing

Sallen-key (VCVS, multiple feedback) second order active filter

Bandpass filter (Sallen-key, State Variable)

Switched capacitor filters, VCF's
Types of OpAmps

Packages (single, dual, quad)

Specs

Voltage, current, R-R

Speed, Gain/bandwidth trade

High Impedance, JFET, CMOS

Noise (current, voltage)

Compensation...
Some examples:

Ancient: 741

Garden variety, out to 200 Khz; not bad for audio either (LF351, TLO81/2/4, OP482/4

A little better: AD711/712/713

Generic, single supply (pulls to ground) LM324 (quad)

Low Power: TLO6x, CMOS: TLC271 series (programmable power), CA3130, CA3140

Low Power, low V, R-R (often CMOS): LPC661IN (National), MAX494 series, OP491, TLC2274 series

" ", but a bit faster: OP462 series

Low voltage, R-R, moderate power, good speed: MAX474/475

Good DC performance (low drift): LM308, OP297/497, OP27

Low noise, Stiff drivers (600 Ohm audio lines), standard in audio: NE5532/5534, TLE2082 series

Low voltage noise: AD743, AD745, AD797 (this one is touchy...)!

Fast OpAmps: LM318, AD817 (video; nice and stable), AD829 (low noise video)

Differential video amps/drivers (not really OpAmps): LM733, NE529 (stability woes... very fast and cheap)

Comparitors (not really OpAmps either...): LM311, LM339 (quad; single supply), CA3290 (CMOS)

Instrumentation amplifiers (" "): Burr Brown INA series, AnalogD's AMP01 (low noise), AD623 (low V, R-R)
OpAmp Variants:

Norton Amplifiers (CDA's): e.g., LM3900

Current-Feedback Amplifiers: e.g., National Comlinear series

Programmable Gain Amplifiers (PGA's): e.g., AD8320, OPA675, OPA676
Discrete Semiconductors (Transistors, FETs, MOSFETs)

Device introductions, i_c = b i_be i_d = g_m v_gs
Examples:

2N2904 (NPN low power), 2N3906 (" "), Ic around 100 mA

MPF102 (N-FET)

VN2222L (low power MOSFET), VN1302N3 (fast LP MOSFET), SuperTex fast power MOSFETs

TIP31 (NPN med. power), TIP32 (PNP med. power)

2N3055 (NPN power), MJE2955 (PNP power)

Look for VCEO, Ic, Beta, ft specs

Emitter Follower and source follower, the Darlington pair Arrays, e.g., ULN2001,2003,2003,2004

Grounded emitter, switch

Notion of biasing for linear operation

High current buffer stages

The power transistor & its offspring

Packages, heat sinks, ratings

Driving lamps, inductive loads, lightbulbs, LED's

Push-Pull drivers

With and without crossover distortion (biasing)

Linearized with feedback around OpAmp

Power OpAmps; e.g. Burr Brown series (OPA663 [80 mA] thru OPA512 [15 A]), APEX

Opposing Differential Drive Stages

Motor Drivers

Push/Pull (linear drive)

H-Bridge (e.g., LMD18200)

Steppers
Thyristors (very quickly...)

SCR's, Triacs, DIACs

The dimmer switch
Power supply regulators

Series regulators (78xx, 79xx)

Low dropout regulators (e.g., MAX883)

Switching regulators, up & down DC/DC converters (e.g., MAX639 series)
Logic

Define a logic signal

Families: TTL, CMOS, HC, F, ECL

Essential gates (NAND, NOR, XOR)

FlipFlops, Latches

Counters

Data selectors, multiplexers, demultiplexers

Switches
Special Circuits

See Maxim, Analog Devices, Burr Brown, Linear Technologies, etc. listings

555/556 timers

8038, 566, XR2206 VCO

Sample/Holds (LF398, AD682/684 [fast, integral cap])

Analog switches (DG201 series from Analog, LF13201 series from National)

Operational Transconductance Multipliers (OTA's): CA3080, LM13700

Barry Gilbert's XAMP (AD600, AD603)

Multipliers (AD633)

Log amplifiers, nonlinear functions

Audio Power Amplifiers, LM386
How to Prototype

Protoboard basics, wiring it up

Power supply connections and care thereof

The short circuit...

Power supply ratings

What is an oscilloscope and how to start using it

The Digital Voltmeter

Instinctive troubleshooting

Check chips/heat, voltages, oscillations, glitches from no filtercaps or too fast a response

Don't put your face near the chips at first turn on until you make sure there's no burning component!
Assignment

Analysis of the sample assignment circuit
Adjourn...