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ABC of electronics terms

(To find chips for distinct functions, see the functional pages.)

S

Scarce chip

Chip for which there is more demand than availability.

local

More

Schematic

See Circuit Schematic.

Sci.Electronics.Repair

Newsgroup on usenet about repairing electronical devices.

• Filip Gieszczykiewicz
• www.repairfaq.org/ELE/HTML/REPAIR/

SCR

Silicon Controlled Rectifier

www.americanmicrosemi.com/tutorials/scr.htm

Scroll Lock Key

On 19990129 Brian G wrote:

Excuse me, I am very familiar with computers and know a lot about them, but this question has always hacked at my brain:
What does the scroll lock key do??!?!?!?!

The scroll lock key is supposed to lock the scrolling process. Scrolling is the fact the old text on the screen (onder DOS for example) is shifted up line-by-line when a new line is added at the bottom. The lock key stops and resumes this process. Use the 'type' command to show a long file and try to stop this using the key...

Under Unix this process was done using the XON and XOFF characters, ctrl-S and ctrl-Q. This also works an a PC sometimes. Some Unix'es also used the ESC key for this, which was much easier since it was a single key that is easy to hit clickly...

SCSI

Small Computer System Interface. Often pronounced as skuzi.

SCSI
www.lsilogic.com/	The SCSI chips of formerly NCR->Symbios->Adaptec
www.scsita.org/	SCSI Trade Association (STA)
metalab.unc.edu/mdw/HOWTO/SCSI-Programming-HOWTO.html	Linux Documentation Project
www.seagate.com/support/kb/disc/ultrascsi.html	Ultra SCSI

Books:

SCSI-Bus und IDE-Schnittstelle. Peripherie-Schnittstellen: Hardware, Protokollbeschreibung, Anwendung

ISBN: 3827314178

DM 80

See also:

ASA

ATAPI

Hard Disk Drive

IDE

SDIF

Sony Digital InterFace

See SPDIF.

SDK

Software Development Kit.

This is a kit of software (and sometimes hardware) that allows you develop software for certain specific hardware. See also IDE (Integrated Software Environment). An SDK usually contains a compiler, assembler, downloader. Sometimes also a debugger and/or simulator. An IDE has all functions integrated into what seems to be one GUI (Graphical User Interface). Borland was one of the first to offer quite serious IDE's (for a low price): Borland's Turbo Pascal).

(currently unknown)

The MWave SDK is there under 'software'

SDLC

Synchronous Data Link Control is an IBM communication link protocol used to implement the System Network Architecture (SNA).

Intel's (in 1978 announced) 8273 can handle this format together with the HDLC format.

Sensor

Electrical device that can measure something non-electrical in it's environment.

See also:

local

Sensor manufacturers

Serial port

A port that sends it's data one bit at a time over a single line.

local	Choosing a UART
www.beyondlogic.org/	About interfacing it
ftp.psyber.com/tcj/faqs/The_Serial_Port	FAQ directory
ftp.psyber.com/tcj/faqs/The_Serial_Port.info	FAQ information
ftp.psyber.com/tcj/faqs/The_Serial_Port.more01	FAQ part 1
ftp.psyber.com/tcj/faqs/The_Serial_Port.more02	FAQ part 2
ftp.psyber.com/tcj/faqs/The_Serial_Port.more03	FAQ part 3
ftp.psyber.com/tcj/faqs/The_Serial_Port.more04	FAQ part 4
ftp.psyber.com/tcj/faqs/The_Serial_Port.more05	FAQ part 5
www.rdrop.com/~cary/html/serialportdocs.html	By David Cary
www.beyondlogic.org/	At 'Beyound Logic'
local	See also
www.lavalink.com/SERIALPARALLELPRODS.HTML	PC boards for sale

Books:

title	order at Amazon USA	price indication
Serial Port Complete	ISBN: 0965081923	$32

Besides the RS-232 protocol there are several other serial busses:

1 wire	Dallas (now Maxim) serial bus	data+clock combined (and ground)
2 wire	Philips I2C bus	data, clock (and ground)
3 wire	Industry standard serial bus	in, out, clock (and strobe and ground)

Servo Motor

If I remember correctly, a servo motor is a motor that has a constant speed, because it's actual speed is being measured and is used to adjust the voltage that drives the motor.

www.rentron.com/servo.htm	Serial Hobby-Servo Controller
www.industrycommunity.com/myforum/stephen_bartlett/	Servodrives and Servomotors Forum: Variable speed drives with/without position control, servodrives with/without position control, drive synchronisers, absolute encoders, fieldbus communications.

See also Stepper motor.

SGML

See PCIS

SIMM

Single In-line Memory Module

www.nctnico.cistron.nl/	Hardware Web: SIMM pinouts
www.midiweb.com/hww/	Hardware Web: SIMM pinouts

Simulator

Software to mimic the electrical behaviour of electrical circuits in order to test them before they are actually build.

Where	Manufacturer
www.cadence.com/	Cadence
www.metasw.com/	hSpice
www.hyperlynx.com/	Hyperlynx
www.mentor.com/	Mentor
www.microsim.com/	PSpice
www.viewlogic.com/	Quad/Viewlogic
www.intusoft.com/	Spice by Intusoft
www.veribest.com/	VeriBest

Book:
High Speed Digital Design: A handbook of Black Magic

title	order at Amazon USA	price indication

Single Board Computer

Complete computer on a single PCB. Generally a complete IBM-PC is meant with this.(These SBC's are build into quite expensive devices, but can save a lot on development costs since they are completely PC-like so the software can be developed and tested on normal low-cost PC's using standard compilers and then easily transfered once the product is ready.)

Where	Manufacturer
www.advantech.com.tw/	Advantech

Sinus

Lowest energy waveform, because it's change is as gradual as possible. Therefore it's a very natural waveform. It's change is also directed by a sinus wave form in turn and the change of the change also, at infinitum (=until forever)...

local	Sinus and cosinus generation
www.interstice.com/~sdattalo/technical/theory/sinewave.html	Theory

SK

www.americanmicrosemi.com/tutorials/ecg_nte_sk.htm

SLDRAM

SyncLink DRAM.

www.sldram.com/

SLDRAM Consortium

Slide

Sliding variable resistor?

Where	Manufacturer
www.accuride.com/	Accuride
www.thomsonind.com/	Thomson

S-Link

Sony's S-Link Technology (Control-A1) is used to connect (Sony) appliances.

www.sony.co.jp/	Sony
www.brouhaha.com/~eric/pic/controls.html
www.geocities.com/CapeCanaveral/Launchpad/4652/sircs.htm

Smart Card IC

IC* used on a smartcard. Smart cards are the newest generation (now in 1997) of credit cards which have intelligent processors on board. ISO-7816 series is the most widely used smart-card-IC standards.

www.smartcardsys.com/	PC/SC specs for coupling with PC, Technical Overview by Phillippe Sarlin
www.visa.com/ .. cardspec.pdf	EMV'96, Standards for card sessions from Europay, MasterCard and Visa
www.gemplus.fr/	Gemplus' excellent site, data + links!
www.gemplus.com/	Gemplus' excellent site, data + links!
www.java.sun.com/	Java Card Forum, promotes Java as Smart Card language
Axiohm	Sells smart card reader/writers for something over $100.

Smart Card IC* vendors:
www.hitachi-eu.com/	Hitachi
www.mot-sps.com/csic/smarcrd/	Motorola
www.mot-sps.com/csic/smartcrd/	Motorola (or this?)
www.necel.com/	NEC
www.semiconductors.philips.com/identification/	Philips
www.siemens.de/	Siemens
www.st.com/	ST
www.ti.com/	TI
www.xicor.com/	Xicor

SMT

Surface Mount Technology

As opposed to the more ancient technique of using through hole pins on chips SMT chips are soldered directly to one side of a PCB. This has several advantages:

• No hole need to be drilled, which saves money. (Only for VIA's...)
• Both sides of the PCB can be used to attach IC*'s to.
• The pins can be much closer together (because there is no minimim drilling width. Because of this the packages can also be much smaller.
• The layout of both sides of the PCB can be done indepently greatly reducing developing and PCB software complexity.

• Trouble shooting and repairing becomes much harder, especially with the J-wing type of pins.
• There is yet another type of IC*'s you need to stock...

A way to desolder SMT is puting a thin wire behind the pins, heat the pins and pulling the wire under the pins one by one. Preferable use a wire that doesn't get soldered itself. Perhaps the lacqered (sp?) wire that they use to wind transformators might work or some metal that isn't easily solder...

How is SMT soldered?

www.smtnet.com/

More info

Socket

Socket (hardware)

A hole where a plug or a set of plugs go into, generally in order to connect wires or connect a wire to a device.

Where	Manufacturer
www.advintcorp.com/	Advanced Interconnect
www.arieselec.com/solution.html	Aries Electronics
www.ca-online.com/	Circuit Assembly Corp
www.hollingsworth.com/	Hollingsworth
www.mill-max.com/	Mill-Max
www.yeu.com/	Yamaichi Electronics

Socket (software)

The connection in software to a channel over a network.

www.pz-oekosys.uni-kiel.de/unix/faq/unix-faq-socket.html

Unix Socket FAQ for Network Programming

Software

local

This item got it's own subdirectory

Solder

Good current conducting mixture of lead and tin that has a low smelting temperature and can be used to join certain metals like copper and is therefore used to connect electronical components.

Where	Manufacturer
www.kester.com/	Kester Solder

See also Desolder and PCB.

Sound Card

A PCB in a PC to record and make sounds with.

It generally has several parts:

• An interface to record and output MIDI data. This is done via an 6850 (?) UART.
• A way to input sound in several formats: 8-bit, 16-bit, Linear, PCM* (A-Law), ADPCM*. (Often only in mono.)
• A way to output them again (also in stereo.)
• A way to generate tones like an electronic organ. This is used to convert MIDI information into music.
• A way to output sound from several inputs like a CD-ROM player.
• (Advanced:) A way to output the sound from the PC itself, so the old beeper... (This to save on parts like an amplifier and a speaker once the soundcard is embedded in the motherboard.)
• A wave table part, which I know little of. I assume the board would need a processor that uses a ROM or RAM to do the dedicated calculations so the main processor of the system can keep 100% of it's time dedicated to playing games.

Current sound cards have generally several historically originated parts:

• The Ad-Lib standard part, which seems to be the most primitive.
• The Soundblaster part, which is also still quite primitive (8-bit).
• The Windows Sound System part (which was really great: 16-bit etc.).
• A Yamaha OPL-2, OPL-3 or OPL-4 part which makes the music. (Also on the SB, I think.)
• The MIDI interface (Probably also in the SB.)

The MS Windows Sound System was based on an AD chip named AD1848 and which was later much improved by Crystal (owned by Cirrus Logic) as CS4231A.
Later chips from these two incorporated also the SB etc. parts.

It's all quite a mess and sometimes the connecting chips are really hard to get data about.

See also:

sound chip (next)
sound file
WAV
maxirc.soundcentral.com/	MaxiSound Resource Center
members.aol.com/cridi/	'I have a dream...' site
www.opensound.com/osshw.html	Open Sound System

Sound chip

See also the voice and speech sections in this ABC...

local

More about sound chips etc.

Sound file

A sound file is a file on a computer system to store sound in.

www.cwi.nl/ftp/audio/

definition of a lot of those file formats

SPDIF

Sony/Philips Digital Interface

local

More

Specifications

See also in this ABC:

cable

connector

ATAPI

EIDE

EISA

IDE

ISA

SCSI

etc.

Speech

Human speech

Computers can try to:

• Record it (generally compressed)
• Play it back
• Recognise it
• Generate it

local	Speech generation
local	Speech Recognition
local	Voice recognition
local	voice recognition chips
local	Voice synthesizers

Speed

The volocity with which something moves, but here we're talking about processor speed, so the number of useful computations a processor can execute per second.

local

Speed comparison between several embedded processors

SPI

(Synchronous) Serial Peripheral Interface

See SPI.

SPICE

SPICE files are used to simulate components using software like PSpice.

nyquist.ee.ualberta.ca/pub/cookbook/spice/	In the Circuit Cookbook
www.maxim-ic.com/TechSupport/spicemod.htm	SPICE models of Maxim chips
local	See also

Spotting

Determining the function of a chip by looking at it's number, the number of pins, the board it's on, where it is on the board and what else is on the board.

local

Tips for chip spotting

Spying

Book:

title	order at Amazon USA	price indication
Electronic Circuits and Secrets of an Old-Fashioned Spy	ISBN: 1581600275	$20

Square root

Mathematical function

local	Square root calculation
www.interstice.com/~sdattalo/technical/theory/sqrt.html	Theory
www.allcode.com/8051/	See SQROOT1.ASM

Square wave

www.interstice.com/~sdattalo/technical/theory/sqwave.html

Theory

S-Record

Motorola's file format for transfering binaries to an embedded environment.Also called S1S9 format.(Intel has a similar format. Tektronix also. And often regular hex dumps are used.)

A Unix document about it.

S-Records are ASCII characters in a protocol developed by Motorola and isused to transfer data and program code to and from host computers or tostore such information. Details of this protocol have been archived as

• nyquist.ee.ualberta.ca/pub/motorola/general/s_record.zip
• ftp.luth.se/pub/misc/motorola/faq/s_record.gz

ST6

Processor made by ST.

local	ST6 page in the Chipdir
ftp.unina.it/pub/electronics/FAQ/st6faq.zip
ftp.unina.it/pub/electronics/FAQ/st6faq.txt
FAQ	if even that file disappears

Stepper Motor

A stepper motor is a motor that only steps a certain arc of a full rotation each time that a voltage is being applied. By feeding the motor pulses you can exactly control how far the axis is being rotated. You can usually rotate the motor in both directions. Stepper motors are for example used for the head movements in plotters, printers and disk drives.

home.t-online.de/home/uwe-wulf/lmd18245.htm

Serial stepper motor driver by Uwe Wulf

See also Servo motor.

Stereo Graphics

Making the eyes see depth by providing them with slightly different images.

www.stereographics.com/html/hdk.htm

Stereo3D Hardware Developer's Handbook

Standard

General specification on how to design a product so it can work together with other similar products.

See also ANSI, CEN, CCITT, DIN, IEEE, IETF, ISO, JEDEC, NEN, NNI

See also:

www.hut.fi/Misc/Electronics/standards.html	In Finland
www.cmpcmm.com/cc/standards.html	Pointers to Computer and Communications Standards
www.us-epanorama.net/standards.html	Standards

Static Electricity

Read this.
us-tech.com/august96/prods/smi/smi024.htm
www.wescorpstaticcontrol.com/products/Ant_Stat_Tape.html

Storage

See also: Harddisk, SCSI, ATA, ATAPI, IDE etc.

alumni.caltech.edu/~rdv/comp-arch-storage/FAQ-1.html

Answers for Frequently Asked Questions for comp.arch.storage

Surge

See local

Surplus

Surplus goods are left-over goods. Surplus goods are generally cheaper then new stuff, but only if you can easily find them. When you have to hire someone to find them for you or if they have to find you, they can be much more expensive than new stuff (in time and or money).

www.bgmicro.com/ - Surplus electronics

SVPC

SVPC Design Conference

Find out the latest in "Breaking the I/O Bottleneck in the PC Architecture" by joining Intel at the 1996 Silicon Valley Personal Computer Design Conference and Expo (SVPC '96), Oct. 7-9 at the Sunnyvale, Calif., Hilton.
In addition to a keynote address, Intel will lead a discussion on standardized Intelligent I/O, the I2O specification, and its impact on the PC.
For more information on SVPC, contact SysTech Research at 408-293-8383 or e-mail systech@ix.netcom.com
www.intel.com/design/news/bottlnk.htm

Switch

A switch is an electrical, electronical or mechanical device to interrupt or conduct an electrical current.

Where	Manufacturer
www.ab.com/mem/	Allen-Bradley
www.apem.com/	Apem
www.mew.com/	Aromat
www.ckcorp.com/ (gone?)	C&K
www.cole-switches.com/	Cole Instrument Corporation
www.cpclare.com/	CP Clare
www.ctscorp.com/	CTS Corp
www.ch.cutler-hammer.com/	Cutler-Hammer
www.eaoswitch.com/	EAO Switches
www.eaton.com/	Eaton Commercial
www.eecoswitch.com/	EECO Switches
www.electro-nc.com/	Electro Switch
www.e-switch.com/	E-Switch
www.grayhill.com/	Grayhill
content.honeywell.com/sensing/	Honeywell
www.switches.com/	Marquardt
www.liteon.com/	Lite-On, International
www.us.liteon.com/	Lite-On, USA
www.liteon-europe.com/	Lite-On, Europe
www.mec.dk/	MEC
www.memtron.com/	Memtron Technologies
www.microswitch.com/	MicroSwitch, now Honeywell Sensing and Control
www.ottoeng.com/	Otto Engineering
www.pui.com/	Projects Unlimited
www.schurterinc.com/	Schurter
www.solico.com/	Solico/MEC
www.switchcraft.com/	Switchcraft

Synchronous circuits

Synchronous circuits are circuits that work in time steps under the control of a clock. At each clock pulse the output state of each stage is propagated to the next stage as input. An example of a synchronous circuit is an MCU or MPU. In contrast in an asynchronous circuiit there is no clock (and usually no registers and flip-flops) and the output of each part is immediately propagated to every part connected to it's outputs. You can regard a synchronous circuit as asynchronous stages with registers between the stages. Synchronous circuits are usually much more complex than asynchronous ones. When only one clock circuit is used for all registers, the slowest stage determines the maximum clock speed. According to RISC philosophy it's therefore important to reduce the propagation delay in each stage (dividing up stages if need be) until all stages take about as much time and as little time as possible.

www.makaton-signs.org.uk/PL-Sequencer/	Using progammable logic for sequencing circuits
local	My article about RISC processor philosophy