Glossary

ACMs Adaptive Computing Machines.
Active components Transistors like NPN, PNP, NMOS, CMOS etc. The specialty of a transistor is that it can amplify, namely yield an output electrical signal bigger than the signal at its input. For this reason these devices are characterized as “active”.
Air gap The gap in the typically doughnut shaped magnetic core of an inductor. The gap width times the area of the doughnut cross section is the volume in which the inductor's energy is stored.
ANSYS ANSYS, Inc.—computer-aided engineering technology and engineering design analysis software products and services.
BCD Bipolar-CMOS-DMOS.
Bipolar The process technology yielding NPN and PNP transistors.
Bipolar circuit A circuit built with bipolar transistors such as NPN and PNP transistors.
Bricks A DC-DC converter built according to industry standard footprint. Examples of form factors are: the popular 1/4 Brick (2.28" × 1.45") and the newly defined 1/16 Brick (1.1" × 0.9").
BOM Bill Of Materials.
Boost A device or technique that produces an output voltage above the input voltage.
Buck converter A voltage regulator that produces an output lower than its input. Also called step down (and sometimes step-down) converter. The term “buck” appears to be just another reference to the lower value of the output or as the American Heritage Dictionary puts it “of the lowest rank in a category.”
Buck xDSP core Step down regulator (buck) for DSP core.
Buffer Transfers voltage transparently from its input to its output while increasing dramatically the current drive.
CDMA Code Division Multiple Access.
Charge pumping The action of biasing the node VCHP above VIN via the capacitor/diode C/D action.
Chip-scale package A package technology that encapsulates the silicon die with minimum overhead, resulting in a final integrated circuit of dimensions virtually identical to the silicon die itself.
CMOS Complimentary Metal Oxide Semiconductor. This is the process technology yielding N-type and P-type MOSFET transistors.
COP Coefficient Of Performance.
CPU Central Processing Unit.
Current mirrors An input/output circuit that produces an output current identical to the input current.
Current source A circuit that produces a constant current invariant to changes of the input voltage.
D flip-flop A logic memory device that transfers to the output (Q) the logic data (D) present at its input when the positive edge of a clock pulse (positive edge triggered DFF) hits the CLK input. A second output (Q/) reproduces an inverted copy of the data present at the Q output.
Darlington stage A cascading of two bipolar transistors (emitter on one transistor connected to the base of the second transistor) yielding an amplification gain equal to the product of the gains of the two single transistors.
Digital control architecture A control architecture in which control parameters (for example control of a motor speed) are immediately digitized and processed digitally thereafter.
Digitally controlled analog system A control architecture in which control parameters (for example control of a motor speed) are processed analogically while the communication with a host controller happens digitally.
Discrete power MOSFET A single MOSFET transistor housed in a three terminal package and built to process high levels of power. “Discrete” refers to its ‘single’ nature and is used as opposed to “Integrated Circuit” which refers to a collection of a high number of transistors on board of a single die.
Disrupting technology A new technology that enters an established market served by an existing technology and gains acceptance thanks to lower cost. Often disrupting technologies start as low cost and low performance technologies and are ignored by the establishment. After a few learning cycles the disrupting technology is better and cheaper than the existing technology, killing it.
DMOS Double Diffused MOS. A special type of power MOSFET transistor.
Doped In order to create semiconductors the atomic structure of silicon is altered (doped) by the introduction of atoms of certain other materials (dopants).
DSP Digital Signal Processing.
DSP Core The processing unit in the DSP, as opposed to the periphery or I/O section.
DSTB Digital Set-Top Box.
Duty cycle The proportion of time during which a component, device, or system is operated. The duty cycle can be expressed as a ratio (0 to 1) or as a percentage (0 to 100%).
EMI Electromagnetic Interference.
Energy management The technique of optimizing energy delivery with minimum waste. For example a voltage regulator can produce a well regulated output voltage and waste a lot of energy in the process due to poor efficiency. Typically it costs more to deliver the same performance with less waste.
ESI Equivalent Series Inductance.
ESR Equivalent Series Resistor.
Feature phones High end cellular telephones equipped with features like camera, secondary display etc.
Flip-flop A digital logic circuit tht can be switched back and forth between two states (high and low, or on and off).
Fly-back converter An isolated converter architecture in which the energy is stored in the air gap of a gapped transformer during the first (active) part of the cycle and transferred to the output in the second part. One of the simplest isolated architectures and it is best suited to handle low levels of power.
Forward converter An isolated converter architecture in which the energy is transferred to the output during the first (active) part of the cycle and stored in the output inductor in the second part of the cycle. This architecture is suited for higher levels of power than the flyback converter.
Foundry houses Chip fabrication facilities that can produce chips for companies that are fab-less.
FSB Front System Bus.
Green mode A mode of operation in which the device consumes less than a Watt in stand-by mode.
Green power Power conversion operation in green mode.
GSM Global System Mobile; a communications standard.
Handset Cellular telephone handset.
Heatsink An electronic device in operation produces heat that needs to be disposed of. This is done by tightly connecting the device to heatsinks, highly thermally conductive materials like aluminum or copper molded in shapes—typically fins—that maximize surface for best disposal of heat by contact with circulating air.
Hooks Connections.
Hysteretic comparator A comparator is a device that changes the state of its output (low to high) when a positively sloped voltage signal applied to its positive input equals a reference voltage level present at its negative input. A hysteretic comparator is one in which the reference voltage is lowered after the signal crosses the reference, thereby providing a margin of safety against electrical noise that could induce false triggering of the comparator.
Inherently fast A circuit that is fast because of its nature. For example a sequential circuit can be said to be inherently slow because it will need several clock cycles before executing a command. Conversely, a hard wired circuit can be implemented for maximum speed.
Integrated circuit A collection of transistors connected to perform a given function all fabricated on a single silicon die.
Interleaved multiphase regulation The paralleling and time spacing of multiple regulators.
Interleaving The act of paralleling and time spacing multiple regulators.
I/O Input/Output.
Kirk effect A dramatic increase in the transit time of a bipolar transistor caused by high current densities.
LCD Liquid-Crystal Display.
LDO Low Dropout Regulator. This regulator can work with a small difference between supply and output voltage.
Leading edge An electric pulse is made of a rising or leading edge a flat top and a falling or trailing edge.
Leading edge modulation In leading edge modulation the control loop time-shifts the pulse's leading edge to change the duty cycle. Conversely in trailing edge modulation the control loop time-shifts the pulse's trailing edge to change the duty cycle.
LED Light Emitting Diode.
Li+ Cell Lithium-Ion cell. The sign “+” is short hand for a (positively charged) Ion.
MCH Memory Channel Hub.
MCU Micro Controller Unit.
Mesa An early type of transistor whose topology resembled that of a broad, flat-topped elevation with one or more clifflike sides, common in the southwest United States.
Microcontroller-based control architecture A voltage regulator architecture in which the control loop is implemented by a sequential machine like a general purpose microcontroller as opposed to dedicated, hard wired circuitry.
Mixed As in mixed signal processes. Processes that are capable of integrating on the same piece of silicon MOS and Bipolar transistors, which typically require different processes.
MOS Metal Oxide Semiconductor
MOSFET Metal Oxide Semiconductor Field Effect Transistors.
Multiphase interleaved buck converter A buck converter resulting from the paralleling and time spacing of multiple regulators.
N-MOS Short for negative-channel metal-oxide semiconductor. A type of semiconductor that is negatively charged so that transistors are turned on or off by the movement of electrons. In contrast, P-MOS (positive-channel MOS) works by moving electron vacancies (holes).
N-type material A semiconductor material like silicon doped with materials from Column V of the periodic table of elements such as phosphorous that have an excess of negatively charged free electrons.
NAND gate Negative AND gate. An AND gate performs the ‘and’ logic function of producing a logic output equal to the product of the logic inputs (like in 1×1 = 1 and 1×0=0). The NAND gate takes the result of the AND gate and inverts it.
OEM Original Equipment Manufacturer.
Opamp Operational Amplifier.
P-MOS Short for positive-channel metal oxide semiconductor. A type of semiconductor that is positively charged so that transistors are turned on or off by the movement of holes. In contrast, N-MOS (negative-channel MOS) works by moving electrons.
P-type material A semiconductor material like silicon doped with materials from Column III of the periodic table of elements such as boron that have an excess of positively charged holes.
Passive components Resistors, capacitors, inductors, diodes etc. A network built only with such components will always yield an output electrical signal smaller than the signal at its input. Because of their inability to amplify signals these components are characterized as ‘passive’.
Peak current-mode control A type of current-mode control in which the value controlled is the current peak.
PFC Power Factor Correction.
PFM Pulse Frequency Modulation.
Poles The complex frequencies that make the overall gain of the filter transfer function infinite.
POL Point Of Load.
Power management The discipline of powering the circuits in an electronic appliance or transforming raw AC line electricity into finely regulated circuits that can power up delicate circuits like microprocessors and DSPs. Power here is counter posed to Signal, the business of providing computing, amplification, video, or audio capabilities.
PSUs Power Supply Units.
PWM Pulse Width Modulator
PWM controller Pulse Width Modulation controller. A type of switching regulator control technique.
Reference voltage A stable, known voltage level that is referred to in order to compare any other voltage level in the application.
RF section Radio Frequency section.
RX block Receiving block.
SDRAM Single Data Random Access Memory.
Serial bus Serial data bus. An I/O port that transfer data serially on one or few wires. As opposed to a parallel data bus.
Set-Reset flip-flop A flip-flop is an electronic circuit that alternates between two states. When current is applied, it changes to its opposite state (0 to 1 or 1 to 0).) A set-reset is on in which activating the “S” input will switch it to one stable state and activating the “R” input will switch it to the other state.
Silver box A metallic box containing all the AC-DC power circuitry necessary to power a personal computer motherboard, and found in any PC box.
SIM card Single In-line Memory cards.
Smart battery A battery incorporating electronics capable of communicating, via a serial bus, its identy, charge status, and other useful parameters to a host microcontroller.
Smart ICs The expression refers to chips with intelligence on board, like CPUs and microcontrollers.
Smart phone A device which would have the advanced functionality of a handheld computing device, a digital still camera, a global positioning system, a music player, a portable television set, a mobile phone, and more in one convergent device.
Smooth Slowly varying.
SMPS Switch Mode Power Supply.
Snub network A network typically made of a low value resistor in series with a capacitor and presenting high impedance in normal operation and low impedance to spurious, fast varying signals, thereby short circuiting them and consequently preventing other networks it is connected to from exposure to such fast varying signals.
SOC System On a Chip.
SOI Silicon On Insulator.
SPICE Simulation Program with Integrated Circuit Emphasis.
SPICE deck A sequence of commands in SPICE language. Commands in ancient electronics times were punched on cards, piled on card decks, and fed to a computer for number cruching.
Sweet point An optimum point of operation that is the best compromise between conflicting requirements like high clock frequency versus high efficency.
Switch mode A mode of operation typical of switching regulators in which the energy transfer from input to output is discontinuous or in buckets. This is opposed to a linear mode of operation typical of a linear regulator in which the energy transfer from input to output is continuous.
TDMA Time Division Multiple Access.
TFT Thin-Film Transistors.
THD Total Harmonic Distortion.
Time to market The time it takes to develop a product and take it to market.
Trailing edge An electric pulse is made of a rising or leading edge a flat top and a falling or trailing edge.
Trailing edge modulation In trailing edge modulation the control loop time-shifts the pulse's trailing edge to change the duty cycle. Conversely in leading edge modulation the control loop time-shifts the pulse's leading edge to change the duty cycle.
TX block Transmitting block.
Valley control Short for Valley current mode control.
Valley current-mode control A type of current-mode control in which the value controlled is the ripple current waveform valley.
Virtual prototype A simulation of a device as opposed to a physical prototype.
VP Voltage Positioning.
VCESAT Voltage between collector and emitter of a saturated transistor, namely one forced into heavy conduction.
VDD Common symbol for a positive power supply voltage.
VLSI Very Large Scale Integration.
Zeros The complex frequencies that make the overall gain of the filter transfer function zero.
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