EDN articles from July 2004

EDN archives from July 2004

Yeah, but, where are you now7.(Leading edge: what's hot in the design community.)
July 8, 2004... "We now have people who perform running commentary on the minutiae of their daily lives as they travel down a grocery line--'Honey, I'm at the avocados'--or round the corner. A favorite New Yorker cartoon tracks a cell-phone narrator through...

CompactPCI computer breaks $1000 barrier.(Leading edge: what's hot in the design community.)(Brief Article)
July 8, 2004... Targeting industrial, transportation, and military applications, the new ICP-CM single-board computer from Inova Computers delivers midrange performance at an entry-level price. Inova based the product on the Intel Celeron M microprocessor,...

TDM operates over PSN without headaches.(Leading edge: what's hot in the design community.)(Brief Article)
July 8, 2004... ZARLINK SEMICONDUCTOR'S new ZL50111 family of TDM-over-IP packet processors meets the protocol requirements in the recently announced ITU-T (International Telecommunications Union Telecommunications) TDM-MPLS (Multiprotocol Label Switching)...

Tool provides hierarchical verification.(Leading edge: what's hot in the design community.)(Brief Article)
July 8, 2004... DESIGNERS KNOW that using a hierarchical approach to circuit design improves the quality of results and often decreases development time. Verification engineers often separately verify blocks of a design before integrating them into circuits to...

Dilbert.(Leading edge: what's hot in the design community.)
July 8, 2004... [ILLUSTRATION OMITTED] Caption: QUESTION: HOW DO YOU KNOW WHICH MANAGEMENT TECHNIQUES WORK BEST? LOGICALLY, DOESN'T THE EXISTENCE OF THOUSANDS OF MANAGEMENT BOOKS SHOW THAT NO ONE KNOWS WHAT WORKS BEST? THE TRICK IS KNOWING WHICH...

Move away from fixed hardware to SPI-4.2.(Leading edge: what's hot in the design community.)(Brief Article)
July 8, 2004... Fulcrum Microsystems' new PivotPoint SPI-4.2 switch chip targets high-performance networking and storage applications. The six-port FM 1010 PivotPoint SPI-4.2 seamlessly interconnects devices such as transceivers, network processors, traffic...

ZigBee now comes in a box.(Leading edge: what's hot in the design community.)(Brief Article)
July 8, 2004... ATMEL HAS introduced a controller, radio, and protocol-stack implementation of ZigBee, a low-data-rate, low-power networked-wireless standard for control and monitoring applications. Atmel based ZigBee on the IEEE 802.15.4 standard, which...

MEMS-design software provides EDA approach.(Leading edge: what's hot in the design community.)(Covento)
July 8, 2004... The integration of electronic and mechanical parts of a system has always been a challenge for designers. Normally, teams using different tools design the two portions of the system, and the integration often occurs only after the vendor...

Dueling graphics juggernauts trade announcement, improvement jabs.(Leading edge: what's hot in the design community.)
July 8, 2004... WITH NVIDIA'S latest graphics flagship now disrobed and in feisty fighting shape, you had to know that ATI Technologies' counterpunch wouldn't be too long in arriving (see "Graphics advancements span PCs to cell phones," www....

Microprocessors offer connectivity options.(Leading edge: what's hot in the design community.)(Freescale Semiconductor)
July 8, 2004... FREESCALE Semiconductor's four new ColdFire families--the MCF547x, MCF548x, MCF523x, and MCF527x 32-bit microprocessor families--comprise more than 20 32 bit microprocessor devices. The MCF547x and MCF548x families are the first to implement...

Devices allow transparent expansion of PCI and PCI-X to PCI Express.(Leading edge: what's hot in the design community.)(Brief Article)
July 8, 2004... PLX TECHNOLOGY has announced its first three PCI Express devices, the PEX 8516 and PEX 8532 switches, supporting 16 lanes with four ports and 32 lanes with eight ports, respectively, and the PEX 8104-to-PCI/PCI-X bridge. The flexible port...

Number of bits versus LSB errors.(baker's best)(LEAST-SIGNIFICANT-BIT)
July 8, 2004... WHAT DO LSB (LEAST-SIGNIFICANT-BIT) specifications mean when you are looking at ADCs? A fellow engineer told me that a 12-bit converter from Manufacturer X had just seven usable bits. So, essentially it was only a 7-bit converter. He based this...

Harnessing the hard-drive metamorphosis.(edn.comment)
July 8, 2004... THE BURGEONING CAPACITIES of 2.5- and 3.5-in. hard drives are having an intriguing effect on PC-software design, providing developers with the means to dramatically improve users' experiences. For example, streaming media players employ...

Achieving the ultimate soundtrack: a portable digital hard-disk recorder brings realistic audio to movie and TV audiences.(how it works)(Zaxcom Inc)(Biography)
July 8, 2004... TODAY'S ENTERTAINMENT audiences have become discriminating. They're not satisfied with anything less than never-seen-before action scenes in feature films and attention-grabbing effects in TV programs, music videos, and even commercials. What...

Waiting for the big gig: Ethernet at 10 GBPS promises to decrease th cost of transporting data, leading to an exploson of new network services. But do we need the bandwidth--even at bargain prices?(Cover Story)
July 8, 2004... FOR YEARS, PEOPLE have cited users' insatiable appetite for more and more data as the primary driving factor for our ever-expanding networks. Each time Ethernet rates have been increased by an order of magnitude, users have quickly consumed the...

Pick a card: the number of memory- and I/O-card formats your systems potentially need to support is increasing. Insight into how the cards may fall will help you select a winning hand.(design feature)
July 8, 2004... THE DIVERSITY OF AVAILABLE memory cards has long complicated your product-definition and -design decisions (Reference 1). But, even though smaller and more obscure formats have faded over the years from the scene, even more formats have...

Power control winning big: back-to-basics knowledge can make AC as easy to control as DC.(techtrends)
July 8, 2004... AS ITALIAN TIRE GIANT Pirelli's advertising reminds us, "Power is nothing without control." But if your application is automotive, consumer, or industrial, embedded control is often worthless without power-handling ability. If you want to...

Divide and conquer complex chip designs: few designers would debate the advantages of using a hierarchical-design approach for developing a complex chip.(design feature)
July 8, 2004... HISTORICALLY, DESIGNERS have used a hierarchical approach to chip design--breaking the chip into pieces, of blocks--to extend the capacity of design-automation tools. Adopting a hierarchical approach has the advantage of enabling concurrent RTL...

16-Bit ADC simplifies current measurements: design note 341.(LTC2433-1)(Analog-to-Digital Converter)
July 8, 2004... Introduction The LTC[R]2433-1 is a high performance 16-bit Delta-Sigma ADC for DC measurements. With an input noise floor of 1.45[micro][V.sub.RMS] and a reference range of 100mV to [V.sub.CC], the input resolution and range can be...

Build a transformerless 12V-to-180V dc/dc converter.(design ideas)
July 8, 2004... SOME TRANSDUCERS for portable or automotive applications need accurately regulated, high-voltage bias and draw little current. To produce such high voltages from a low battery voltage, designers typically use switch-mode dc/dc...

Build a simple one-chip phototimer.(design ideas)
July 8, 2004... RECENTLY, I NEEDED to automatically switch on a lamp when it became dark and keep it on for a given time. Trying not to reinvent the wheel, I looked through what was available on the market, but I could not find an inexpensive device that...

Solenoid trip circuit works at battery's end of life.(design ideas)
July 8, 2004... THIS DESIGN IDEA involves a low-power motion-detector circuit that operates flora battery power for extended times. Part of the design includes a solenoid-operated trip mechanism that triggers whenever it detects motion. The drive circuit for...

Servo loop improves linear-regulator efficiency.(design ideas)(Product Enhancement)(Product Application)
July 8, 2004... LINEAR REGULATORS are easy to implement and have better noise and drift characteristics than switching approaches. Their largest disadvantage is inefficiency: excess energy dissipated as heat. Several well-known techniques are available to...

Boole helps simplify wiring and save money.(design ideas)
July 8, 2004... TO SAFELY OBSERVE the positions of two cylinders, you need two signals: one circuit, X, which is open only when both cylinders are in a safe position (two normally closed switches in parallel), and one circuit, Y, which is closed only when both...

Thick-film chip resistors.(Passives)(Brief Article)
July 8, 2004... * Standard passivated (CHP) and high-frequency (HCHP) resistors cover resistance values of 0.1 [ohm] to 100 M [ohm] with 0.5% tolerance * 100-ppm/[degrees]C temperature coefficient versions are available from 10 [ohm] to 5 M [ohm] *...

Self-shielding inductors.(Passives)(HM55 series)(Brief Article)
July 8, 2004... * Offer an inductance range of 0.4 to 6.0 [micro] H in three standard through-hole package sizes * HM55 series, 32 to 59 cents (100,000) * Handle de current to 40A BI Technologies 1-714-447-2759 www.bitechnologies.com

Conformal coated RF chokes.(Passives)(Brief Article)
July 8, 2004... * Come in a package that is just 0.10 in. in diameter and 0.16 in. long * Provide an inductance range of 0.10 to 470 [micro]H, a dielectric strength of 500V rms, a self-resonant frequency to 300 MHz, and an operating-temperature range...

Low-profile power inductors.(Passives)(PG0155 series)(Brief Article)
July 8, 2004... * Provide a current rating as high as 24A with ah inductance range of 0.30 to 2.30 [micro] H and a dc resistance range of 2.2 to 16.5 m [ohm] * Come in a 11 X 10.4 x 3.7-mm package with a thermal tolerance of 150[degrees]C * PG0155...

Fixed attenuator pads.(Passives)(Brief Article)
July 8, 2004... * Tiny 0.030 X 0.030 X [x]0.010-in. chips come in attenuation values from 1.0 to 30 dB * Offer power-handling capability of 2W (CW) and temperature coefficients of resistance of less than 100 ppm/[degrees]C * GroundWrap attenautor...

Current-sense resistors.(Passives)(Brief Article)
July 8, 2004... * Achieve resistance values from 0.001 to 0.500[ohm] in tolerances to [+ or -] 1% and temperature coefficients of resistance of less than [+ or -]100 ppm/[degrees]C * Offer a choice of surface-mount case sizes ranging from 0402 to 2512 ...

ETX computer board.(Embedded Systems)(Brief Article)
July 8, 2004... * Supplies a Pentium M processor, memory Subsystems, sound, SVGA, Ethernet, and standard PC I/O on an ETX form factor * Plugs into an application-specific baseboard to create semicustom solutions for embedded designs * ETX-701, from...

Linux board-support package.(Embedded Systems)(Brief Article)
July 8, 2004... * For use with DY 4 Systems' SVME/DMV-182 dual PowerPC single-board computer * Includes a full Linux distribution, TimeStore IDE, certified GNU tool chains, symmetrical multiprocessing support, kernel enhancements, and modules that pro...

PC/104 sound card.(Embedded Systems)(Sonic Audio SP)(Brief Article)
July 8, 2004... * Sound Blaster Pro-compatible card records, synthesizes, compresses, stores, and plays back voice, sound, and music * Furnishes two supplemental serial ports and a parallel port * Sonic Audio SP, $104 (100) Parvus Corp ...

EBX controller card.(Embedded Systems)(Brief Article)
July 8, 2004... * Onboard GPS timing synchronizes data acquisition to within 190 nsec * Provides as many as 32 16-bit ADC channels and four 14-bit DAC channels, as well as a Pentium core * SBC2596, from $925 Micro/sys Inc 1-818-244-4600 ...

PCI-X Single-slot carrier.(Embedded Systems)(Brief Article)
July 8, 2004... * Allows PCI-X systems to be tested at 133 MHz without violating the stringent loading restrictions of the bus specification * Works with the Vanguard PCI/PCI-X network bus analyzer * Vanguard PCI-X carrier, $9920 Vmetro Inc ...

Portable server/workstation.(Embedded Systems)(Acme Portable Machines Inc)(Hercules HTII-767)(Brief Article)
July 8, 2004... * Houses a 17-in. flat-panel LCD and 150 Gbytes of storage in a portable chassis * Employs a seven-slot back-plane with a choice of ATX motherboards * Hercules HTII-767, $3600 (10) with a 3-GHz processor Acme Portable Machines Inc...

14-bit arbitrary waveform generator.(Test and Measurement)
July 8, 2004... * PCI card generates signals to 125M samples/sec on two channels * Comes with 8 to 256M samples of onboard memory * UF6031, $5558 to $12,985 Strategic Test Corp 1-617-621-4010 www.strategictest.com

Thermocouple converter.(Test and Measurement)(Pico Technology Ltd UK)(EL041)(Brief Article)
July 8, 2004... * Accepts four thermocouple inputs, expandable to 40 channels * Operates over--270 to + 1820[degrees]C, accurate to within 0.3%[+ or -] 0.5[degrees] C * EL041, $380 Pico Technology Ltd UK +44-1480-396395 www.picotech.com

PXI frequency counter.(Test and Measurement)(Brief Article)
July 8, 2004... * Furnishes eight frequency-measurement channels on a single-width 3U module * Monitors a variety of pulse sources in a frequency range of 0.06 Hz to 100 kHz * P635, from $4795 KineticSystems Co 1-800-328-2669 ...

PCI analog-output board.(Test and Measurement)(Brief Article)
July 8, 2004... * Provides eight 16-bit analog output channels with a [+ or -]10.1V output range * Includes eight bidirectional digital-I/O lines * PCI-DAC6702, $599 Measurement Computing Corp 1 508-946-5100 www.measurementcomputing.com

Boundary-scan/flying-probe upgrade.(Test and Measurement)(APT-9000 series)(Brief Article)
July 8, 2004... * Integrates boundary-scan testing with Takaya's APT-9000 series flying-probe testers * Provides greater fault cover age on complex analog/digital circuit boards * Symphony APT 9000, less than $25,000 JTAG Technologies Inc. ...

Rubidium-frequency standard.(Test and Measurement)(Brief Article)
July 8, 2004... * Uses an autoadaptive disciplining algorithm that tracks a one-pulse/sec source *Provides 10-and 5-MHz sine-wave synthesized output, and stability of [+ or -]5 x [10.sup.-11] per month * Model 2965AR, $3995 Novatech Instruments...

PCI-communication analyzer.(Test and Measurement)(Brief Article)
July 8, 2004... * Provides 105M-sample/sec simultaneous sampling on two input channels with 14 bits of vertical resolution * Comes with as much as 1G sample of onboard acquisition memory * CompuScope 14105, from $5995 Gage Applied Inc Canada...

EPIC computer features GPS, data acquisition, and expansion.(leading edge)(Brief Article)
July 22, 2004... THE RECENTLY introduced 486/586-based SBC4495 single board controller flora Micro/sys comes in the new 4.5 x 6.5-in. EPIC (Embedded Platform for Industrial Computing)-standard footprint. The board includes a temperature-compensated...

C tool provides algorithmic synthesis.(leading edge)
July 22, 2004... SYSTEMC USERS MUST translate their designs into either Verilog or VHDL to implement the necessary digital circuitry. Some tools provide this translation, but no equivalence-checking tool exists to verify the translation. To execute the...

Fuel-cell battery pack gets a step closer.(leading edge)(MTI)(Brief Article)
July 22, 2004... MANY TECHNICAL and market-channel obstacles stand in the way of achieving fuel-cell-based power packs for cell phones, laptops, and similar mass-market items (see "Fuel-cell technology: The glass is half full... with methanol fuel," EDN, May...

Book helps you get your hands dirty and your mind moving.(leading edge)(Brief Article)(Book Review)
July 22, 2004... WHAT'S NOT TO LIKE in a book entitled Hardware Hacking: Having Fun While Voiding Your Warranty? Edited by Joe Grand, this $39.95, 448-pg book (ISBN: 1-932266-83-6) guides you in taking apart, modifying, and enhancing your hard drive, PDA, Apple...

Dilbert.
July 22, 2004... WRITE A REBUTTAL TO THIS TECHNICAL RECOMMENDATION SO I CAN REJECT IT. [ILLUSTRATION OMITTED] I CAN'T WRITE A REBUTTAL TO MY OWN RECOMMENDATION! [ILLUSTRATION OMITTED] ... THEN I HAD TO WRITE MYSELF UP FOR INSUBORDINATION. ...

Processors squeeze size and cost.(leading edge)(Brief Article)
July 22, 2004... Microchip's PIC10F family of 8-bit microcontrollers pushes the floor for device size and cost. The small form factor of the six-pin SOT-23 package enables you to use these microcontrollers in space-constrained applications and can help reduce...

SystemC users get more support.(leading edge)
July 22, 2004... THE LACK OF a complete automated design flow has hampered engineers using SystemC to implement an algorithm or to design a product architecture. They have had either to manually recode the SystemC implementation in Verilog or VHDL or to rely on...

Reliable multicast bolsters unreliable wireless and wired applications.(leading edge)
July 22, 2004... THE NEW DFBroadcast 2.0 reliable multicast library from Digital Fountain targets both wireless-broadcast and wired-multicast applications in commercial and enterprise networks. The company based the...

Next-generation graphics target high-end apps.(leading edge)
July 22, 2004... WILDCAT GRAPHICS BOARDS from 3Dlabs have long dominated in markets in which performance and features are kings, price is a secondary consideration, and customers are too few to attract serious attention from volume-motivated competitors. The...

LED with concave lens yields even output.(Brief Article)
July 22, 2004... LEDtronics built its latest high-intensity discrete LED with a concave lens, so the 5-mm-wide T1-3/4 device delivers light that is even from the center to the edge. This lens spreads the inherently collimated light beam, resulting in a...

Connecting layers.(signal integrity)
July 22, 2004... I'M IN TUCSON, AZ, VISITING RAYTHEON. Digital engineer Jose Guttierez approaches me after class, wanting to know why I've suggested stitching together all of the ground planes in his board with a carpet of vias. He needs an intuitive, simple...

Thinking outside that box.(edn.comment)
July 22, 2004... ONE OF THE DRAWBACKS of being an editor is that we easily become jaded. We see so many innovative products and smart people who give us a show and tell that we soon find ourselves saying "been there, seen that" to even genuinely interesting and...

Hack this: as hackers move down the food chain form desktops to embedded systems, hardware- and software- security decisions dominate the design process.(Cover Story)
July 22, 2004... FIVE YEARS AGO, billions of embedded systems moved into the spotlight as pundits predicted Y2K failures that would disrupt manufacturing, power distribution, transportation, communications, water purification, cash dispensing, and weapon...

On the gold in PON: PON (Passive Optical Network) access technologies can reflect the value of higher order network structures.(design feature)
July 22, 2004... A SIMPLISTIC VIEW of ultra-long-haul WAN, long-haul WAN, and MAN holds that the three communication-network structures are fractal relatives. All apply similar strategies to the exploitation of finite physical media and their corresponding...

Digital-diagnostic-monitoring functions for optoelectronic transceivers: for some commonly cited analog signals in optoelectronic transceivers, engineers must analyze the impact that errors have.(design feature)
July 22, 2004... A recent revision to the optoelectronic-transceiver module MSA (multisource agreement) adds digital diagnostic-monitoring requirements to the transceiver (references 1 and 2). Digital diagnostic monitoring provides a user with critical...

Dual Smart Battery charger simplifies battery backup for servers: design note 342.(Advertisement)
July 22, 2004... Introduction Smart Batteries are an increasingly popular choice for more than just traditional compact consumer electronic devices. For example, Smart Batteries are being used as battery backup for products such as blade servers, where...

Delta-sigma ADCs high performance analog solutions from linear technology: automatic calibration of external components.
July 22, 2004... The LTC[R]2449, an 8kHz, 16-channel delta-sigma ADC, provides high resolution systems designers with a dramatic improvement in accuracy, precision and drift. The device reduces the cost and increases the performance of precision designs by...

Memories to the for: using bare dice for flash-memory systems: developing a reliable, cost-effective memory subsystem using known good dice requires careful planning.(design feature)
July 22, 2004... A GROWING TREND among mobile-memory-system developers is to stack dice vertically in a package. Designers use this method to save board space on small pc boards, which increasingly find use in compact end-user products, such as mobile handsets....

High-side current monitor operates at high voltage.(design ideas)
July 22, 2004... THE SIMPLEST technique for measuring current in an actuator or a motor is to monitor the ground current with a resistive element between the load and the ground. Because the device and its associated electronics share a ground potential, you...

Digital potentiometers enable programmable biquadratic filter.(design ideas)
July 22, 2004... OF THE MANY TYPES of analog filters available to designers, few allow easy adjustments of the filter parameters. The biquadratic, or biquad, filter is an exception, however. You can change that filter's corner frequency ([[omega].sub.o], Q, and...

High-current supply uses standard three-terminal regulator.(design ideas)(Brief Article)
July 22, 2004... VOLTAGE-REGULATOR design for high output currents can be a critical and difficult task. Although voltage regulators with 1A maximum output current are simple to design, thanks to 78xx three-terminal voltage regulators, at output currents higher...

Synchronous flyback circuit provides high-efficiency conversion.(design ideas)
July 22, 2004... BUCK REGULATORS are usually the first choice when you design non-isolated step-down regulators unless the ratio of [V.sub.IN] to [V.sub.OUT] greater than 10, the input voltage is high, or both. Low duty cycle can be problematic for FET drivers...

Discrete semiconductors.(components showcase)
July 22, 2004... Automotive-trench MOSFETs * Logic-level gate-drive devices simplify power management in door modules, window lifts, and lighting, as well as in under-the-hood systems, such as ABS * All five 40 and 55V parts are Q101-qualified and have...

Computers & peripherals.
July 22, 2004... Dual-layer DVD recorder * 12 X USB 2.0 drive stores as much as 8.5 Gbytes on one DVD+R double-layer disc * Provides buffer under-run protection for reliable burns * Super DVD Writer, $249.95 MSRP Iomega Corp, 1-888-446-6342,...

Microprocessor.
July 22, 2004... 32-bit single-chip microcontrollers * Flash-and mask-ROM devices are based on the MIPS R3000A architecture with selectable 32- or 16-bit fixed length instructions * Offer three independent 32-bit execution units (ALU, MAC, and...

Welcome to ... the best of design ideas.(Letter from the editor)
July 22, 2004... GIVEN THE COMPETITIVE NATURE OF THE ELECTRONICS industry, the Design Idea section of EDN used to puzzle me. Engineers gladly send us solutions to tricky design problems with only the prospect of praise from their peers as reward (and a few...

Bootstrapping allows single-rail op amp to provide OV output.(The best of amplifiers)(Brief Article)
July 22, 2004... MANY SINGLE-SUPPLY-POWERED applications require amplifier-output swings within 1 mV--or even submillivolts--of ground. Amplifier-output-saturation limitations normally preclude such operation. Figure 1's power-supply bootstrapping scheme...

Absolute-value circuit delivers high bandwidth.(The best of amplifiers)
July 22, 2004... MOST ABSOLUTE-VALUE CIRCUITS have limited bandwidth and high component count, and they require several matched resistors. The circuit in Figure 1 uses three fewer components than most absolute-value circuits require, and only two of the...

Single IC provides gains of 10 and -10.(The best of amplifiers)(Integrated Circuits)
July 22, 2004... REAL-WORLD DATA-ACQUISITION systems require amplifying weak signals to match the full-scale input range of an A/D converter. Unfortunately, when you configure them as gain blocks, most common amplifiers have both gain errors and offset drift....

One-shot provides frequency discrimination.(The best of communication)
July 22, 2004... You USE A FREQUENCY DISCRIMINATOR to compare one signal frequency with another one. A functional feature, retriggering, of a monostable, one shot 74xx123 multivibrator can yield frequency discrimination. Figure 1 shows a frequency discriminator...

High-current driver serves home-power-line modems.(The best of communications)
July 22, 2004... HOME-BASED POWER-LINE networking signals are similar to xDSL signals in that they both typically employ a form of OFDM. Both applications require high output current, wide bandwidth, and good linearity. This Design Idea describes a simple...

Circuit ensures safety in power-on operation.(The best of controllers)(Brief Article)
July 22, 2004... DURING POWER- AND START-UP sequences (booting), the outputs of industrial control systems may yield uncontrolled pulses before the soft ware defines the correct status. If these outputs control the power-on state of a system, these uncontrolled...

Microcontroller provides SRAM battery backup.(The best of controllers)(Static Random Access Memory)
July 22, 2004... TO MAINTAIN CONTENT IN A POWER loss, many designs that include SRAM require a dedicated device that can automatically switch from a standard power supply to battery operation. Microcontrollers ([micro]Cs) seldom find use in power-switching...

Thermal switches provide circuit disconnect.(The best of detectors)(Brief Article)
July 22, 2004... A SINGLE TEMPERATURE SENSOR can provide an interrupt to a microcontroller when the measured temperature goes out of range. You need multiple temperature sensors when you have to monitor more than one hot spot. A microcontroller implements the...

Circuit offers improved active rectification.(The best of detectors)
July 22, 2004... RECTIFIERS CONVERT AC SIGNALS to dc. You can combine a diode and a load resistor to create a half-wave rectifier, provided that the amplitude of the ac source is much larger than the forward drop of the diode (typically 0.6V). Unfortunately,...

Prevent instrumentation-amp RF-rectification errors.(The best of filters)(designing RF filters)
July 22, 2004... INSTRUMENTATION AMPLIFIERS SERVE in a variety of applications that need to extract a weak differential signal from large common-mode noise or interference. However, designers often overlook the potential problem of RF rectification inside the...

Primary side controller for half-bridge intermediate dc bus converters.(Design Tip)
July 22, 2004... A simple open-loop primary side control for bridge-type isolated intermediate bus converters is based on the integration of a fixed 50% duty cycle oscillator with a 100V half-bridge driver to deliver a complete primary side control and drive....

Build an adjustable high-frequency notch filter.(The best of filters)
July 22, 2004... ALTHOUGH YOU CAN OBTAIN UNIVersal, resistor-programmable switched-capacitor filters that are configurable as notch filters, most cannot operate at bandwidths higher than 100 kHz. Further, the typically 16 to 20-pin packages do not include a...

DirectFET[TM] package drain connection increases buck converter power density.(Design Tip)(Brief Article)
July 22, 2004... International Rectifier HEXFET[R] MOSFETs in the DirectFET[TM] package are unique devices in which the silicon die attaches directly to the PCB. The source and gate connections are on one side of the die and the drain contact is on the other...

Grounded resistor tunes oscillator.(The best of oscillators)
July 22, 2004... TO VARY THE FREQUENCY OF ANY sine-wave oscillator, you should use a pair of ganged variable resistors, and you should thoroughly match their characteristics over the entire variation range to satisfy the oscillator's balancing conditions. This...

Frequency source feeds entire lab.(The best of oscillators)(Brief Article)
July 22, 2004... PLUMBING A LAB WITH A STANDARD frequency makes a lot of sense if the lab uses multiple frequency counters, spectrum analyzers, and other frequency-dependent test equipment. Rather than spending time keeping all of the instruments' oscillators...