Download Electronic Control and Digital Electronics Student`s Book: FET FIRST

Student’s Book
Student’s Book
FET FIRST
FET FIRST
Level 3
Level 3
ElectronicAuthor
Control and
Author
Digital Electronics
NQF Level 4
Student's Book
R. van Heerden , S. Jowaheer, R. Jonker
FET FIRST Electronic Control and Digital Electronics
NQF Level 4 Student’s Book
© R. van Heerden, S. Jowaheer, R. Jonker 2009
All rights reserved. No part of this publication may be reproduced,
stored in a retrieval system, or transmitted in any form
or by any means, electronic, photocopying, recording,
or otherwise, without the prior written permission of the
copyright holder or in accordance with the provisions
of the Copyright Act, 1978 [as amended].
Any person who does any unauthorised act in relation to this
publication may be liable for criminal prosecution and civil
claims for damages.
First published 2009 by
Troupant Publishers (Pty) Ltd
P O Box 4532
Northcliff
2115
Distributed by Macmillan South Africa (Pty) Ltd
Typeset by: Marie Eksteen
Edited by: Jeannie van den Heever
Cover design by Brandtalk
ISBN: 978-1-920311-25-4, eISBN: 978-1-430801-67-2
It is illegal to photocopy any page of this book without written permission from the publishers.
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Contents
Topic 1 Replacing faulty components on PC boards . . . . . . . . . . . . . . . . . . . . . . 1
Module 1 Safety precautions and procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Unit 1.1: Safety procedures when soldering and desoldering on a PC board. . . . . . . . . . . . . . . . . . . . . 2
Unit 1.2: Desoldering and soldering components on a PC board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Unit 1.3: Handling circuit boards containing MOSFET components . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Module 2 Reading and interpreting semiconductor manuals . . . . . . . . . . . . . . . . . . . . . . . . . 13
Unit 2.1: Finding and interpreting the operational limits of semiconductor devices in manuals . . . . 13
Unit 2.2: Looking up replacement parts in manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Module 3 Constructing basic electronic circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Unit 3.1: Revision of RLC circuits and resonance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Unit 3.2: Timing circuits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Unit 3.3: Filter circuits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Unit 3.4: Oscillator circuits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Unit 3.5: Inverting power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Unit 3.6: Designing, constructing and testing circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Topic 2 Binary decoding and loading software onto a computer. . . . . . . . . . . . 63
Module 4 Binary code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Unit 4.1: The binary system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Module 5 Software loading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Unit 5.1: Software loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Unit 5.2: Problems affecting computer software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Topic 3 PLCs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Module 6 Synchro-servo motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Unit 6.1: Symbols used in synchro-servo motors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Unit 6.2: The operation and construction of synchro-servo motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Unit 6.3: Applications of synchro-servo motors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Module 7 Designing and fault-finding simple control circuits. . . . . . . . . . . . . . . . . . . . . . . . . 119
Unit 7.1: Introduction to PLCs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Unit 7.2: Simple ladder logic diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Unit 7.3: Basic fault-finding in PLCs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
PoE Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Glossary
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Module 1: Module title
iii
Topic 1
Replacing faulty
components on PC
boards
Module1
Safety precautions and
procedures
Overview
Strict safety procedures and a logical method must be followed when
you service or repair an electronic device. You must also ensure that
you use the correct tools. Make sure that you know precisely where
the fault is and whether you must replace components or not. If you
have to replace components, have the correct components at hand.
Units in this module
Unit 1.1: Safety procedures when soldering and desoldering on a PC
board
Unit 1.2: Desoldering and soldering components on a PC board
Unit 1.3: Handling circuit boards containing MOSFET components
Unit 1.1 Safety procedures when
soldering and desoldering on a PC
board
Unit outcomes
By the end of this unit, you will be able to:
• demonstrate safety procedures to be followed when soldering and
desoldering on a PC board and on a viro board.
Safety procedures
When you replace components on a PC board, there are two
procedures that take place, namely desoldering and soldering. You
will learn more about these procedures in Unit 1.2. There are many
safety procedures or practices that you should follow when replacing
components. Here are some of the most important safety practices.
General safety practices
• Remember that water is a conductor of electricity. Avoid coming
into contact with water when working with electricity and when
using a soldering iron.
• Take care when using an extension cord. Make sure it is in good
condition and that the earth connection is not corroded or dirty.
• Never carry out maintenance or repairs on moving or rotating
machinery.
2
Module 1: Safety precautions and procedures
• Be careful when fault-finding on live equipment. If possible, always
use an isolating transformer to supply the device with power.
• You cannot tell whether an electrical conductor or terminal is live
just by looking at it – always assume that everything is live until
proven otherwise.
• Obtain the required authorisation before you start working on
equipment.
• Make sure you have emergency numbers at hand and know who to
contact in case of an emergency.
Safety practices when soldering
• Make sure that the soldering iron is properly earthed.
• Heat is the most obvious danger when soldering. Solder starts to
melt at around 250 °C but the iron tip needs to be hotter than this to
ensure a good flow of solder. Always place the soldering iron on the
soldering stand when not soldering.
• Use a sponge to clean the tip of the soldering iron. Do not throw
the melted solder off the tip of the soldering iron as it may land on
someone else.
• Always switch off the equipment and soldering iron when you
leave the workbench.
• Keep children out of the room while the soldering iron is hot.
• If you do not wear spectacles, then wear eye protection.
• Solder is a mixture of lead and tin. Lead is poisonous so do not put
the solder in your mouth.
• Always secure your work so that it does not move while you are
soldering as this will affect the accuracy of your work. Various
holding frames are available to hold printed circuit boards.
• Some capacitors can remain charged up to high voltages even after
the power is disconnected. You will hurt yourself if you discharge
capacitors with your fingers. You can also damage the electronics if
you spill solder or multicore desolder wick across the circuit board,
and inadvertently connect a charged-up capacitor to a sensitive
chip. Give capacitors time to discharge before you carry out any
work on the equipment.
• Be careful not to cut your fingers on the wires underneath the
circuit board. The machine-cut edges of metal covers and base
plates are also extremely sharp.
• You present a danger to semiconductors. If you wear synthetic fibre
clothing, walk across a nylon carpet or do anything to acquire a
charge of static electricity, you can discharge several thousand volts
into the circuit. (See Unit 1.3.)
Assessment activity 1.1
Work on your own.
Write an essay describing how you would prepare a work area when you wanted to do
maintenance on a PC board. List at least 10 safety precautions that you would follow when
planning to replace components on the PC board.
Module 1: Safety precautions and procedures
3
Unit 1.2 Desoldering and soldering
components on a PC board
Unit outcomes
By the end of this unit, you will be able to:
• demonstrate the manual dexterity needed to remove and replace
various components on a PC board.
Terminology
Study the following definitions of terms related to soldering and
desoldering:
• alloy: a metal made by combining two or more metallic elements,
especially to give greater strength or resistance to corrosion
• arcing: when a luminous electrical discharge occurs between two
points
• brazing: a process also called hard soldering, in which a filler metal
is melted at a temperature above 450 °C but below the melting
point of the base metals to form a joint between two base metals
• clamp: device used to join, grip, support or compress mechanical or
structural parts
• cold joint: a dull, poorly soldered joint that does not provide good
conductivity
• conduction: the transmission of heat or electricity across matter
• conductivity: the measure of a material’s ability to conduct heat or
electric current
• desoldering: the removal of solder and components from a circuit
for troubleshooting and repair purposes
• flux: a substance that facilitates soldering, brazing and welding by
chemically cleaning the metals to be joined
• hand soldering: soldering that is performed manually with a
soldering iron
• heat transfer: the passage of thermal energy, or energy in the form
of heat, from a hot to a cold body
• joint: the point at which two pieces of metal make contact and are
bonded together with solder
• lead: a soft, heavy, toxic and malleable metal often used in solder
• oxidation: a material’s chemical reaction with oxygen, causing rust
and tarnish to form on metal surfaces
• PCB: printed circuit board used to mechanically support and
electrically connect electronic components, using conductive
pathways called traces etched from copper sheets laminated onto a
non-conductive surface
• resin-based: flux composed of resin, a substance derived from the
sap of some trees and other plants
• short circuit: an interruption in the intended flow of electricity,
especially when current flows short of reaching a device and that
causes excess current flow
4
Module 1: Safety precautions and procedures
• solder:a fusible metal alloy, with a melting point or melting range
below 450 °C, that is melted to join metallic surfaces
• soldering:a process in which a filler metal is melted at
temperatures below 450 °C to form a joint between two base metals
• solderingiron: a tool used to transfer heat to a metal surface to melt
solder and form a joint or circuit; most soldering irons resemble a
large pen
• solderingironstand:a non-flammable stand on which to place a
hot soldering iron
• tinning:the action of applying a trace amount of solder to the tip of
the soldering iron to facilitate the heat transfer process
• toxic:poisonous or harmful; lead is considered to be highly toxic
Desoldering and removing components
from PC boards
Remember to apply all safety procedures, whether you are removing
or adding a component to a PC board.
There are different types of PC boards:
Words &
Terms
• Single-sidedboards
• Double-sidedboards
• Multi-sidedboards.
You are going to work only with single-sided boards. Components
mounted on a single-sided board are normally soldered to the tracks
at the bottom of the board. You have to desolder the components to
remove them from the board. Desoldering is the removal of solder
and components from a circuit board for troubleshooting and repair
purposes. You may want to remove a component to correct an error, to
modify the circuit or to replace a faulty component.
braid: threads wo
ven into
a band
Tools required
Firstly, you will need some special tools to perform this task. These
tools include:
•
•
•
•
•
•
•
•
asolderingironandstand(Fig.1.1)
solder(Fig.1.2)
adesolderingpump(Fig.1.3)
desolderingbraid (Fig. 1.4)
long-nosepliers(Fig..1.5)
wirecuttersorsidecutters(Fig.1.6)
helpinghandsorapanavice(Fig.1.7)
asmallflat-tipPhillipsscrewdriver(Fig.1.8).
Module 1: Safety precautions and procedures
5
Fig. 1.1 Soldering iron and stand
Fig. 1.2 Solder
Fig. 1.4 Desoldering braid
Fig. 1.7 Helping hands
6
Module 1: Safety precautions and procedures
Fig. 1.3 Desoldering pump
Fig. 1.5 Long-nose pliers
Fig. 1.8 Flat-tip screwdriver
Fig. 1.6 Wire or side
cutters
Rules for desoldering components
The first rule for desoldering components is:
The board is more important than the component you are replacing .
Always sacrifice a component before risking damage to the PC board.
It is much easier and less costly to replace a component than to try
to repair or replace a damaged PC board. Sometimes the tracks are
actually as thin as a human hair! Double-sided boards are even more
difficult to work on.
The second rule for desoldering components is:
Do not overheat the solder joints .
Overheating a solder joint can damage the PC board by causing a pad
or trace to detach.
Procedure for desoldering components
Step1: Locate the solder joints for the component that you want to
desolder. This can be a difficult task on a densely populated board.
You want to be certain that you locate the correct joints so that you do
not damage other components needlessly.
Step2: When you have located the correct solder joints, remove as
much of the solder as possible using a desoldering pump. The goal
is to remove as much of the solder as possible. Place the tip of your
soldering iron on the solder joint so that when the solder melts it heats
both the lead and the pad. At the same time, position the tip of the
desoldering pump so that it sucks up the molten solder. Trigger the
pump when the solder has melted.
The trick is to heat the solder joint sufficiently to melt all the solder
on the pad and in the hole. Since this takes some judgment, you will
only become more proficient with practice. PC boards that have plated
through-holes will need to be heated a little longer thean normal
solder pads. Do not overheat the solder pads.
Perform this procedure on all the solder joints holding the component.
In some cases, especially with components that have only one or two
leads, you may find that you have removed enough of the solder so
that the component is loose and can be easily removed. However, this
does not often happen and you should not try to force the component
off the board.
You can also use desoldering braid instead of the soldering pump.
Place the desoldering braid flat against the solder pad. Place the tip of
the soldering iron on the desoldering braid. When the braid becomes
sufficiently hot, you will see it wick up the excess solder. Remove the
soldering iron from the braid and the braid from the solder pad at the
same time. The pad will appear tinned but should be free of excess solder.
Words &
Terms
wick: draw up by
capillary
action
Step3: The next step is to cut the component’s leads on the component
side of the board by carefully using the wire cutters. This is where you
sacrifice the component if necessary to avoid damaging the board. The
goal is to remove the component leads from the board, one at a time.
Module 1: Safety precautions and procedures
7
Step 4: When you have removed the component, heat each solder joint
and remove the lead from the hole with the long-nose pliers. See which
side of the board has the most exposed lead. Hold the lead with the
long-nose pliers. Place the tip of the soldering iron against the pad and
the lead. This must be done on the bottom side of the board unless the
board is double-sided or has plated through-holes. Remove the lead
when the solder has melted.
Step 5: Now remove any remaining solder from the holes using the
desoldering pump. Place the soldering iron against the pad while
holding the desoldering pump against the hole. This usually works
better if you can hold the desoldering pump on the opposite side of
the board from the soldering iron. If you have a board holder, it will
leave both hands free to perform this step. Trigger the pump when
the solder has melted. Remove the remaining solder so that the hole
is open. You can now insert the new component on the PC board and
start the soldering process.
Note that you must first remove the solder before you cut off the
component leads. The reason for this is that, when you snip the
component leads, you are applying stress to the board that may
damage it by lifting a pad or trace. By removing the excess solder, you
minimise the component’s mechanical connection to the board and
reduce the chance of damage.
It is difficult to remove integrated circuits from boards, especially
boards with plated through-holes, even when you have the correct
tools, because the solder goes all the way through the hole. In these
cases, it is better to cut off all the leads of the IC and remove them one
by one to avoid damaging the PC board.
Soldering components onto PC boards
Soldering is the process of joining less fusible metals by using a lowmelting alloy, especially one based on tin and lead.
All parts including the iron tip itself must be clean and free from
contamination. Solder will not take to dirty parts. Old components or
copper board can be difficult to solder because of the layer of oxidation
which builds up on the surface of the leads. This repels the molten
solder. This becomes evident when the solder beads into globules
going everywhere except where you need them. Dirt is the enemy of a
good-quality solder joint.
Step 1: Secure the board so that it does not move during soldering and
affect your accuracy. Various holding frames are available to hold a PC
board.
Step 2: Insert all the parts on one side first and hold them in place with
a special foam pad to prevent them from falling out. Turn the board
over and snip off the wires with cutters before you start soldering the
joints.
Step 3: Before you start soldering, prepare the soldering iron,
especially if it is a new iron. You must first tin the bit. Switch on the
8
Module 1: Safety precautions and procedures
iron and allow the tip to heat up. As soon as it is hot enough, start
melting resin core solder over the bit. Allow the melted solder to drip
off while turning the iron over to coat all sides. The point on the tip
where the resin core is placed is the place where the flux best cleans
and coats. Wipe the solder off the tip with a moist sponge and then
repeat the process. The point where the tip is tinned is the place where
the solder will take to the bit from now on. The rest of the bit will
eventually tarnish. If you want the bit to hold a lot of solder and have
a large heating contact area, tin it halfway up. If you want a tip that
holds only a little solder with a small contact area, just tin the tip of the
tip. An old bit can get burnt, which prevents the solder from taking to
it. Rub a piece of chalk into an old file and use it to clean the bit. You
can then re-tin the bit. Use an old file because solder gets stuck in the
teeth of the file.
Step 4: To solder a joint, first feed a little bit of solder onto the tip to
create a heat-conducting area. Then place the tip on the joint. Try to
ensure that the tip is in contact with both parts of the joint. Feed the
solder onto the joint where the two parts meet, not onto the tip of the
iron. In some cases, it is necessary to feed the solder to the point where
the tip of the iron meets the joint.
Tin all wires and terminals before you put them together and solder
them. Leads of components such as capacitors, resistors, transistors
and ICs do not need tinning since they are already tinned.
Study Fig. 1.9 to Fig. 1.10. Take note of good and bad soldering joints
and also the way to mount components on a PC board.
Terminal
Right
Solder
CC lead
Too little solder
Just right
Wrong
Too much solder
Solder
CC lead
Base material
Fig. 1.9 Good and bad soldering joints
Module 1: Safety precautions and procedures
9
Solder integrated circuits or small transistors as quickly as possible
using a low temperature, as excessive heat will damage them. You
can clamp paper clips over the pins of ICs to drain heat away while
soldering or to prevent static damage to CMOS clips while handling.
(See Unit 1.3 for handling CMOS components.)
Assessment activity 1.2
Work on your own.
1. Describe briefly the procedure for desoldering components.
2. Describe briefly the procedure for mounting components on a
PC board.
3. Demonstrate both these activities practically in the workshop.
Unit 1.3 Handling circuit boards
containing MOSFET components
Unit outcomes
By the end of this unit, you will be able to:
• demonstrate what precautions to take when handling circuit boards
containing MOSFET components.
MOSFET and CMOS devices
The FET or field-effect transistor is a three-terminal device which
performs basically the same function as a bipolar transistor but has
slightly different characteristics. A development of the standard FET
is the metal-oxide semiconductor field-effect transistor or MOSFET.
These transistors have special characteristics which make them more
sensitive to charges and static voltages. A further application of the
MOSFET is the complementary-symmetry metal oxide semiconductor
or CMOS made by combining the P-MOS and the N-MOS transistors.
These devices need careful handling. Although you know by now that
you must take reasonable care when handling all components, certain
components, in particular the MOSFET and CMOS devices, can be
damaged by high-voltage static charges. It is easy for static charges to
occur without evidence of their presence because they are generated
by friction between insulating materials and because so many different
plastic materials with very low conductivity are commonly used every
day. For example, if you walk across a nylon carpet from the door to
the desk in a room, you can easily accumulate a static charge of several
hundred volts. You know that with people it is the current that kills
but with electronic devices it is the voltage that is lethal.
MOSFET devices can be damaged by voltages as low as 250 V, so the
first precaution to observe is to ensure that you are not carrying a
10
Module 1: Safety precautions and procedures
Fig. 1.10 How to mount components
on a PC board
static charge. A person handling such devices in the course of his or
her daily work may have an earthed mat on the bench and an earthed
wrist strap to allow any charge to leak away. You can also earth your
body momentarily before handling these devices. For example, you
can touch the metal casing of any earthed electrical appliance which is
plugged in but not switched on, for example a cold soldering iron.
MOSFET and CMOS devices are supplied in a type of conductive
packaging which may be simply aluminium foil or carbon-filled plastic
foam. Shielding bags are sometimes used but the plastic tubes marked
antistatic are not very effective. Handle ICs packed in these shielding
bags with extra care.
A sensible way to avoid damaging these devices is to use IC holders
and to insert the devices only when construction is complete and
the layout has been checked. Plastic insertion and removal tools are
inexpensive and are preferable to fingers for manipulating the devices.
No device should be inserted while power is applied to the circuit.
Also make sure that the device is inserted the right way round.
Internal protective diodes which limit voltages at the inputs to a safe
level are built into the device as part of its internal construction, but
care is still advisable when handling it.
Words &
Terms
FET: a three-term
inal
device called a fie
ld-effect
transistor which
performs
basically the sam
e function
as a bipolar trans
istor
but has slightly di
fferent
characteristics
MOSFET: a metal
-oxide
semiconductor fie
ld-effect
transistor with sp
ecial
characteristics wh
ich make
it more sensitive
to charges
and static voltage
s
CMOS: a complem
entarysymmetry metal
oxide
semiconductor m
ade by
combining the PMOS and
the N-MOS trans
istors
Some components are affected by heat. For example, resistors change
their value when heated and extreme heat can damage semiconductors
such as diodes and transistors. The best way to avoid such damage is
toacquireasoundsolderingtechnique.Ifthesurfacesbeingsoldered
are clean, you need only apply the soldering iron to the joint for a
short time. The temperature rise in the body of the component will
then be too small to cause any damage. You can buy soldering stunts
to clip on transistor leads during soldering operations, but they are
unnecessary. Rather use a pair of flat-nose pliers when you need to
prevent heat from being conducted to a sensitive device.
Assessment activity 1.3
Work in groups of five.
1.
2.
3.
What is a MOSFET device?
Write a paragraph of about 100 words on how to handle MOSFET devices.
What is the main cause of failure in a MOSFET device when handled and how can you prevent
this from happening?
Module 1: Safety precautions and procedures
11
Summary
• When you replace components on a PC board, there are two procedures that take place, namely
desoldering and soldering.
• There are many safety practices that you should follow when replacing components.
• Desoldering is the removal of solder and components from a circuit board for troubleshooting
and repair purposes.
• The first rule for desoldering components is that the board is more important then the component
you are replacing.
• The second rule for desoldering components is to avoid overheating the solder joints.
• Soldering is the process of joining less fusible metals by using a low-melting alloy, especially one
based on tin and lead.
• MOSFET and CMOS devices need careful handling as they can easily be damaged by highvoltage static charges. It is easy for static charges to occur because they are generated by friction
between insulating materials and because so many different plastic materials with very low
conductivity are commonly used every day. It is therefore recommended that you earth your
body momentarily before handling these devices.
Summative assessment
Work in pairs.
1. Demonstrate how to desolder and solder components on a PC board, using the correct safety
procedures.
2.Write a report on why you followed the safety procedures when desoldering and soldering the
components.
12
Module 1: Safety precautions and procedures
Module 2
Reading and interpreting
semiconductor manuals
Overview
When you service or repair an electronic device, you must be
able to use component manuals. Sometimes the exact component
is not available. You can then use a manual to look up possible
replacements. You will have to use your knowledge to select this
replacement. It is therefore important that you know how to read
these manuals and where to find the applicable information.
Units in this module
Unit 2.1: Finding and interpreting the operational limits of
semiconductor devices in manuals
Unit 2.2: Looking up replacement parts in manuals
Unit 2.1 Finding and interpreting
the operational limits of
semiconductor devices in manuals
unit outcomes
By the end of this unit, you will be able to:
• show how to find the operational limits of any semiconductor using
technical manuals
• interpret the data found in technical manuals.
Introduction
Electronic components are manufactured by many different
companies. Two transistors manufactured in the UK and the USA
may have two different numbers but exactly the same characteristics.
Manufacturers publish the characteristics of their components in
manuals. There are therefore as many different manuals as there are
manufacturing companies. Different countries also have different
identification systems.
It is impossible to deal with all the different manuals in this book. The
Internet is a good place to start when trying to familiarise yourself
with different types of identification systems.
Module 2: Reading and interpreting semiconductor manuals
13
Numbering systems
American numbering system
The United States uses the 1N-prefix for diodes and the 2N-prefix
for all types of transistors, SCRs and triacs. Table 2.1 shows examples
of diodes and their parameters while Table 2.2 gives parameters for
transistors. Table 2.3 is a sample of explanatory notes for transistors.
These parameters are the most common ones and the manufacturers
usually show them in their data manuals.
Type
Reverse
voltage
Forward
current
Power
dissipation
Forward
voltage
Casing
1N 277
120 V
-
-
<1.0 V
DO-7
1N 278
60 V
-
-
<1.0 V
DO-7
1N 283
25 V
-
-
<1.0 V
DO-7
1N 695
20V
100 mA
-
<1.0 V
DO-7
1N 695 A
25 V
150 mA
-
<0.5 V
DO07
1N 994
8V
20 mA
-
<1.0 V
DO-7
1N 995
15 V
30 mA
-
<0.5 V
DO-7
1N 996
25 V
50 mA
-
<0.8 V
DO-7
1N 3466
40 V
75 mA
-
<1.0 V
DO-7
Table 2.1 Examples of the American numbering system for germanium diodes and
their parameters
14
Module 2: Reading and interpreting semiconductor manuals
Transistor
number
PM
OA
LT
PACKAGE
Lead
info
VCB
Max
VCE
Max
VEB
Max
IC
Max
TJ
Max
PTOT
FT
Min
C08
Max
HFE
HFE
Bias
USE
MFR
EURO
EQUIV
USA
2CY17
2CY18
2CY19
2CY20
2CY21
PG
PG
PG
PG
PG
TO5
TO5
TO5
TO5
TO5
LO4
LO4
LO4
LO4
LO4
70V
50V
50V
40V
40V
-
12V
12V
12V
12V
12V
500MA
500MA
500MA
500MA
500MA
100C
100C
100C
100C
100C
240MWF
240MWF
240MWF
240MWF
240MWF
500K
500K
750K
500K
650K
40P
40P
40P
40P
40P
35/140
30/110
60/235
50/145
90/250
500MA
500MA
500MA
50MA
50MA
AMH
AMG
AHG
AMG
AMG
TIS
TIS
TIS
TIS
TIS
ACY17
ACY18
ACY19
ACY20
ACT21
-
2CY22
2G101
2G102
2G103
2G104
PG
PG
PG
PG
PG
TO5
TO5
TO5
TO18
TO18
LO4
LO4
LO4
LO1
LO1
20V
15V
15V
15V
15V
15V
15V
15V
15V
12V
1V
1V
2V
3V
500MA
20MA
20MA
50MA
50MA
100C
100C
100C
100C
100C
240MWF
100MWF
100MWF
300MWF
300MWF
400K
180M
200M
200M
200M
40P
5P
5P
5P
5P
20/210
20MN
20MN
20MN
20MN
500MA
2MA
2MA
10MA
10MA
AMG
RLA
RLA
RLS
RLS
TIS
TIS
TIS
TIS
TIS
ACY22
ASZ21
ASZ21
ASZ21
ASZ21
2N2273
2N2273
2N2273
2N2273
2G106
2G110
2G210
2G220
2G221
PG
PG
PG
PG
PG
TO18
TO5
TO3
TO3
TO3
LO1
LO4
LO5
LO5
LO5
18V
36V
60V
40V
60V
15V
15V
60V
40V
60V
4V
2V
20V
30V
30V
100MA
50MA
6A
10A
10A
100C
100C
100C
100C
100C
150MWF
300MWF
75WH
80WH
80WH
60M
100M
200K
200K
200K
5P
5P
-
30MN
15MN
25/90
10MIN
10MIN
10MA
50MA
5A
10A
10A
RLA
RLS
AHA
AHG
AHG
TIS
TIS
TIS
TIS
TIS
AF124
ASZ21
ASZ15
ASZ16
ASZ15
2N990
2N2273
2N1533
2N1536
2N1533
2G222
2G223
2G224
2G225
2G226
PG
PG
PG
PG
PG
TO3
TO3
TO3
TO3
TO3
LO5
LO5
LO5
LO5
LO5
80V
40V
60V
40V
40V
80V
40V
60V
40V
40V
30V
30V
30V
30V
30V
10A
15A
15A
15A
20A
100C
100C
100C
100C
100C
80WH
80WH
80WH
80WH
80WH
200K
200K
200K
200K
200K
-
10MN
10MN
10MN
10MN
10MN
10A
15A
15A
15A
20A
AHH
AHG
AHG
AHG
AHG
TIS
TIS
TIS
TIS
TIS
ASZ16
AUY29
AUY29-5
AUY29-5
AUY29-5
2N1533
2N1167
2N1167
2N1167
2N1167
2G227
2G228
2G229
2G230
2G231
PG
PG
PG
PG
PG
TO3
TO3
TO3
TO3
TO3
LO5
LO5
LO5
LO5
LO5
60V
80V
40V
60V
80V
60V
80V
40V
60V
80V
30V
30V
30V
30V
30V
20A
20A
25A
25A
25A
100C
100C
100C
100C
100C
80WH
80WH
80WH
80WH
80WH
200K
200K
200K
200K
200K
-
10MN
10MN
10MN
10MN
10MN
20A
20A
25A
25A
25A
AHG
AHG
AHG
AHG
APG
TIS
TIS
TIS
TIS
TIS
AUY29-5
AUY29-5
AUY29-5
AUY29-5
AUY29-5
2N1167
2N1167
2N1167
2N1167
2N1167
2G240
2G301
2G302
2G303
2G304
PG
PG
PG
PG
PG
TO3
TO1
TO1
TO1
TO1
LO5
LO1
LO1
LO1
LO1
80V
20V
20V
30V
30V
80V
20V
20V
30V
30V
1V
10V
10V
10V
10V
3A
300MA
300MA
300MA
300MA
65C
100C
100C
100C
100C
25WH
200MWF
200MWF
200MWF
300MWF
7M
3M
7M
3M
7M
12P
15P
15P
15P
40MN
30MN
45MN
30MN
45MN
500MA
1MA
1MA
1MA
1MA
RPA
RLS
RLS
RLA
RLA
TIS
TIS
TIS
TIS
TIS
Al103
OC44N
OC44N
OC44N
OC44N
2N2147
2N2614
2N2614
2N2614
2N2614
2G306
2G308
2G309
2G319
2G320
PG
PG
PG
PG
PG
TO1
TO1
TO1
TO5
TO5
LO1
LO1
LO1
LO4
LO4
20V
20V
20V
30V
30V
20V
20V
20V
20V
20V
10V
10V
10V
3V
3V
300MA
300MA
300MA
200MA
200MA
100C
100C
100C
85C
85C
300MWF
300MWF
300MWF
225MWF
225MWF
12M
3M
12M
1M
1M
15P
15P
15P
50P
50P
90MN
40MN
120MN
20MN
30MN
1MA
120MA
120MA
20MA
20MA
RLA
RLS
RLS
ALA
ALA
TIS
TIS
TIS
TAD
TAD
OC44N
OC44N
OC44N
ACY17
ACY17
2N2614
2N2614
2N2614
2N1176
2N1176
2G321
2G322
2G323
2G324
2G344
PG
PG
PG
PG
PG
TO5
TO5
TO5
TO5
TO1
LO4
LO4
LO4
LO4
LO2
30V
16V
16V
16V
15V
20V
16V
16V
16V
15V
3V
3V
3V
3V
10V
200MA
100MA
100MA
100MA
100MA
85C
85C
85C
85C
225MWF
150MWF
150MWF
150MWF
150MWF
2M
1M
2M
2M
8M
50P
50P
50P
50P
12P
50MN
25MN
30MN
50MN
50MN
20MA
1MA
1MA
1MA
1MA
ALA
ALA
ALA
ALA
RLA
TAD
TAD
TAD
TAD
TIS
ACY17
ACY17
ACY17
ACY17
OC44N
2N1176
2N1176
2N1176
2N1176
2N2614
2G345
2G371
2G374
2G376
2G377
PG
PG
PG
PG
PG
TO1
TO1
TO1
TO1
TO1
LO2
LO2
LO2
LO2
LO2
15V
20V
20V
30V
60V
15V
20V
20V
30V
60V
10V
10V
10V
10V
10V
100MA
300MA
100MA
300MA
300MA
85C
90C
85C
85C
85C
150MWF
200MWF
150MWF
150MWF
150MWF
2M
1M
1M
1M
1M
12P
40P
40P
40P
40P
25MN
25MN
60MN
30MN
30MN
1MA
1MA
1MA
100MA
100MA
RLA
ALA
ALA
ALG
ALG
TIS
TIS
TIS
TIS
TIS
OC44N
AC126
AC126
AC126
AC126
2N2614
2N2431
2N2431
2N2431
2N2431
2G381
2G382
2G383
2G384
2G385
PG
PG
PG
PG
PG
TO1
TO1
TO5
TO5
TO5
LO2
LO2
LO4
LO4
LO4
20V
20V
70V
50V
50V
15V
15V
30V
25V
25V
3V
3V
12V
12V
12V
400MA
400MA
100MA
100MA
100MA
85C
85C
85C
85C
250MWF
250MWF
250MWF
250MWF
250MWF
1M
1M
1M
1M
1M
50P
50P
70P
70P
70P
75MN
75MN
40MN
55MN
100MN
300MA
300MA
50MA
50MA
50MA
AMG
AMG
ALG
ALG
ALA
TIS
TIS
TIS
TIS
TIS
AC128
AC128
ACY17
ACY17
ACY17
2N2705
2N2705
2N1176
2N1176
2N1176
2G386
2G387
2G395
2G396
2G397
PG
PG
PG
PG
PG
TO5
TO5
TO5
TO5
TO5
LO4
LO4
LO4
LO4
LO4
40V
40V
30V
30V
30V
20V
20V
15V
20V
15V
12V
12V
20V
20V
20V
100MA
100MA
200MA
200MA
200MA
85C
85C
85C
85C
85C
250MWF
250MWF
150MWF
150MWF
150MWF
1M
1M
2M
4M
6M
70P
70P
18P
18P
18P
55MN
100MN
20MN
30MN
40MN
50MA
50MA
10MA
10MA
10MA
ALA
ALA
RLS
RLS
RLS
TIS
TIS
TAD
TAD
TAD
ACY17
ACY17
ASY27
ASY27
ASY27
2N1176
2N1176
2N1305
2N1305
2N1305
2G398
2G401
2G402
2G403
2G524
PG
PG
PG
PG
PG
TO5
TO12
TO12
TO12
TO5
LO2
LO9
LO9
LO9
LO4
105V
20V
20V
40V
40V
60V
20V
20V
40V
30V
40V
3V
3V
3V
15V
200MA
10MA
10MA
25MA
500MA
85C
85C
85C
85C
85C
150MWF
100MWF
100MWF
100MWF
225MWF
800K
40M
40M
60M
1M
30P
5P
5P
5P
40P
30MN
25MN
50MN
50MN
15MN
1MA
1MA
1MA
1MA
1MA
ALA
RLA
RLA
RLA
AMG
TAD
TIS
TIS
TIS
TAD
ACY17
AF124
AF124
AF124
ACY17
2N1176
2N990
2N990
2N990
2N1176
2G525
2G526
2G527
2G577
2G605
PG
PG
PG
PG
PG
TO5
TO5
TO5
TO5
TO5
LO4
LO4
LO4
LO4
LO4
45V
45V
45V
70V
30V
30V
30V
30V
30V
20V
15V
15V
15V
20V
20V
500MA
500MA
500MA
500MA
200MA
85C
85C
85C
85C
85C
225MWF
225MWF
225MWF
225MWF
150MWF
1M
1M
1M
1M
4M
40P
40P
40P
40P
18P
30MN
30MN
40MN
30MN
40MN
1MA
1MA
1MA
1MA
5MA
ALG
ALG
ALG
ALG
RLA
TAD
TAD
TAD
TAD
TAD
ACY17
ACY17
ACY17
ACY17
ASY27
2N1176
2N1176
2N1176
2N1176
2N1305
2G1024
2G1025
2G1026
2G1027
2N21
PG
PG
PG
PG
PG
TO5
TO5
TO5
TO5
TO22
LO4
LO4
LO2
LO4
L37
70V
70V
70V
70V
100V
40V
40V
40V
40V
-
20V
20V
20V
20V
-
500MA
500MA
500MA
500MA
40MA
85C
85C
85C
85C
85C
225MWF
225MWF
225MWF
225MWF
120MWF
1M
1M
1M
1M
1M
40P
40P
40P
40P
-
15MN
20MN
30MN
40MN
-
1MA
1MA
1MA
1MA
-
ALA
ALG
ALG
ALG
ALS
TAD
TAD
TAD
TAD
OBS
ACY17
ACY17
ACY17
ACY17
OC77N
2N22
2N23
2N24
2N25
2N26
PG
PG
PG
PG
PG
-
-
-
-
-
-
-
-
-
-
-
-
PCT
PCT
PCT
PCT
PCT
OBS
OBS
OBS
OBS
OBS
-
2N1176
2N1176
2N1176
2N1176
2N1176B
-
Table 2.2 Examples of the American numbering system for transistors and their parameters
Module 2: Reading and interpreting semiconductor manuals
15