# What are abbreviations used in electrical engineering?

This question is meant to be a glossary of abbreviations used in electrical engineering.

Some abbreviations are very common and universal, and are therefore acceptable to use on this site. Others are quite localized or pet abbreviations used by individuals without a wide following, so are not acceptable on this site. One purpose of this question is to list all abbreviations so that others have a chance to decode them if encountered, but thru voting also show which ones are acceptable to use in a wide international context or not.

So here are some rules to make this question work:

1. Each answer must only be for ONE abbreviation.

2. This will be community wiki, so only ONE answer for each abbreviation. If you want to expand on a description, edit the existing answer for that abbreviation.

3. This is going to get long, so consistant formatting will help. For each answer (abbreviation), start with just the abbreviation within HTML "h1" and "/h1" tags on a line by itself.

4. Upvote answers for abbreviations you think would be acceptable to use in a post on this site without any expansion or explanation.

5. Downvote abbreviations (answers) you think should not be used "bare" on this site. This will be community-wiki, so nobody will loose reputation as a result. In this special case, you are voting on the universality of the abbreviation, not on the quality of the writeup. If you don't like the write up, fix it instead.

# INDEX

A - A(2) AC(7) ADC(15) ALU(3) AM(7) ASCII(12) ASIC(6) ASK(1) AWG(7)

B - BCD(5) BJT(16) BLDC(4) BNC(6) BPF(1) BW(3)

C - CAD(5) CAN(7) CC(1) CC-II(-1) CCCS(1) CCD(6) CMOS(16) CMRR(1) COG(0) CPLD(4) CPM(-1) CPU(7) CRO(-1)

D - DAC(15) DC(7) DEMUX(2) DFT(2) DIP(5) DLL(2) DMA(7) DRC(3) DSO(3) DSP(13) DTFT(0) DVD(-10) DVM/DMM(4)

E - ECL(4) EDA(6) EE(7) EEPROM(13) EMC(3) EMS(-7) EOS(0) EPROM(3) ESD(9)

F - F(2) FDNR(-3) FET(17) FFC(2) FFT(6) FIFO/LIFO(7) FM(7) FPGA(9) FSK(1) FSM(4)

G - GBW(5) GIC(-1) GND(16) GPIO(9) GPS(4)

H - H(2) HDTV(-11) HF(4) hFE(2) HPF(2) HVSP(-1) Hz(3)

I - i(-1) I/P(-7) I2S(1) IC(11) IF(4) IFT(1) IGBT(9) IGFET(0) ISP(4) I²C(13)

J - j(-1) JFET(10) JTAG(7)

K - KCL(6) KVL(6)

L - LCD(17) LED(19) LF(3) LPF(4) LSB, MSB(2) LUT(5) LVD(-1) LVDS(5) LVDT(0) LVS(-2)

M - MCU(6) MEMS(6) MIDI(4) MOSFET(17) MPU(-1) ms(2) MUX(6)

N - NEXT(-6) NPN(12) NTSC(0) NVM(0)

O - O/P(-7) OCXO(2) OLED(4) OP-AMP(8) OTA(3)

P - P-P(0) PAL (logic)(2) PAL (television)(0) PC(-1) PCB(17) PCBA(-5) PCM(4) PFM(-2) PIC(0) PID(9) PLL(9) PM(0) , duplicate(0) PNP(14) POR(3) PPM(-1) PSK(5) PUT(-1) PWM(24)

Q - QM(-6) QVGA(0)

R - RADAR(0) RAM(12) RF(5) RFID(6) RGB(4) RJ45(6) ROM(3) RTL (discrete logic)(2) RTL (Verilog)(2)

S - SAW(3) SCR(9) SD,SDHC(0) SDCC(-3) SMA(4) SMPS(9) SMT(5) SNR(5) SOC/SoC(5) SPI(13) SPICE(8) SRAM(6) SRPP(-2) STA(0)

T - TBH(-8) TCXO(2) THD(6) TRF(-1) TTL(10) TVS(4)

U - UART(12) UHF(4) UJT(0) UL(3) USART(4) USB(4)

V - V(2) VCA(1) VCC / VEE / VDD / VSS(14) VCCS(1) VCO(5) VCXO(3) VFD(3) VGA(-2) VHDL(7) VHF(5) VLSI(2) VNL,VFL(-1) VSWR(4)

W - W(2)

X - XO(1) XOR(3) XTAL(5)

Ω - Ω(0)

186 answers - Sun May 11 09:17:28 2014 (CET)

# NVM

Non Volatile Memory such as fuse or flash based, retains data after power loss.

# HDTV

High-Definition Television

# VGA

• Video Graphics Array technically. :) – JYelton May 1 '14 at 3:56
• And while it originally referred to a particular display adapter board for a PC, it now refers generically to the video interface it defined: 15-pin high-density D-sub connector, discrete analog RGB signals, TTL sync signals, etc. – Dave Tweed May 1 '14 at 23:14

# PCBA

Printed Circuit Board Assembly; a PCB (Printed Circuit Board) with components fitted and ready for use.

• PCBA. Never heard the acronym PCA. – Nick Alexeev Apr 30 '14 at 15:45
• We use PCA at my work all the time. – dext0rb Apr 30 '14 at 22:40

# MPU

Microprocessor or Multi-core processor or Memory protection

• Which part of this is incorrect? – Roh Apr 30 '14 at 16:50
• Check remarks #4 and #5 about voting on this question in the original question. – jippie Apr 30 '14 at 19:45
• @jippie Thanks. – Roh May 1 '14 at 3:31

# LVDT

Linear Variable Differential Transformer

# PUT

Programmable Unijunction Transistor

# CC

"CC" is short for Constant Current.

• Ambiguous, should be spelled out. – Ben Voigt May 1 '14 at 15:59
• @BenVoigt Sometimes you can't help what's printed on the front of your bench-top power supply. – Jonathon Reinhart May 3 '14 at 6:30
• I agree with Jonathon, I have two such different supplies on my desk, different brands, both are using the abbreviations "CC" and "CV". – Lundin May 5 '14 at 11:14

# EOS

Electrical Over Stress: Damage to a device due to a current or voltage that is beyond the specification limits of the device

• EOS is the proper terminology and not ESD control. – user41144 May 1 '14 at 23:29

# LVS

Layout Versus Schematic: A method for verifying the functionality of a layout with the schematic/netlist of the design.

• DRC is voted up, LVS is voted down!! – hassansin May 1 '14 at 16:02

# UJT

Unijunction Transistor. A relatively obscure type of transistor not used much today (2014).

# IGFET

Insulated Gate Field Effect Transistor.

This is a less commonly used name for a MOSFET. But the "insulated gate" terminolgy is used for the IGBT.

# TBH

Take Back Half. An alternative for a PID control loop.

http://www.edn.com/design/analog/4325740/Temperature-controller-has-take-back-half-convergence-algorithm

# I/P

This is short for "input".

• The very reason for starting the question ;o) – jippie May 1 '14 at 17:58
• In electronics, IP most often stands for Internet Protocol suite or IP number. Less often as Intellectual Property or some such, used for CPU or SoC blocks. I've never seen it used for "input" though. – Lundin May 5 '14 at 11:54

# O/P

This is short for "output".

• The very reason for starting the question ;o) – jippie May 1 '14 at 17:59

# XO

"XO" is short for "Crystal Oscillator".

## NEXT

Near End Crosstalk, a concept in full-duplex communication links.

# HVSP

High Voltage Serial Programmer. Programming mode used to program (Atmel AVR) devices that have been fuse protected for reading / writing. It uses 12 V at a certain pin, hence "high" voltage.

## Ω

SI symbol for ohm, abbreviated as:

## kΩ

Kilohm - one thousand (103) ohms

## MΩ

Megohm - one million (106) ohms

## GΩ

Gigaohm - (109) ohm

• @jippie removed – tcrosley May 1 '14 at 7:28
• This is a unit not abbreviation. -1 because I think it should be removed. – Kamil May 3 '14 at 17:31
• @Kamil Yes, I agree Ω is a unit. kΩ is an abbreviation, otherwise it would be written as kilohm all the time (and k by itself, as in 100k with the ohms implied, is certainly an abbreviation). I deleted the initial entry for Ω and just left the other three entries, which are abbreviations. – tcrosley May 3 '14 at 17:42
• So shall we add all this for SI units? Volts, amperes, watts, henries, farads... ? – Kamil May 3 '14 at 17:46
• @Kamil Yes, actually I have already, along with their abbreviations. I agree that for example H is an SI symbol, but mH for example is an abbreviation, which is what this question is all about. – tcrosley May 3 '14 at 17:51

# CPM

Continuous Phase Modulation

# IFT

The Inverse Fourier Transform (IFT) is used in general to mean the action of taking frequency-and-phase data (be it a finite set of values, as in the DFT, or a function on continuous space as in the DTFT or CTFT), and turning it into time-domain data. (or spatial domain, etc., depending on context)

# PAL (television)

Phase Alternating Line, a colour encoding system for analogue television, mainly used in Europe.

# COG

Chip-on-glass. Refers to a technique where an integrated circuit is mounted on and integrated with a glass surface, to save space. This technique is commonly used for integrating a controller IC inside a display.

# LVD

May refer to one of the following:

Low Voltage Detect. A detection mechanism used on microcontrollers, that generates a chip reset when the voltage falls below a given reference level.

Low Voltage Directive. The European directive 2006/95/EC which regulates the behavior of electrical devices with a supply voltage between 50V to 1000V AC, or 75V to 1500V DC.

Low Voltage Differential Signaling, see LVDS.

# NTSC

National Television System Committee, but generally refers to their specification for OTA TV broadcasting. The video signal requires 6 MHz of bandwidth and is broadcast at 29.97 fps with 525 interlaced lines, of which only 483 are visible.

# PFM

Pulse Frequency Modulation. Often generated by older mechanical systems that would send a single pulse for each rotation (or fraction) of a shaft. A hall detector counting gear teeth is another common use.

# PPM

Pulse Position Modulation.

A modulation scheme widely used in optical communication in which the position of the carrier pulse is changed according to the information.

• Also "parts per million" – jippie May 9 '14 at 19:22

# PIC

May stand for 2 types of devices, which are not related to each-other.

• Peripheral Interface Controller.

• A family of micro-controllers from Microchip Technology.

# j

Imaginary number. Math uses i but EE uses that letter to represent current.