December 4, 1997

Hot 100 Products of 1997 (North America)

Small module simplifies unlicensed-RF-transmitter design.

A family of low-power transmitters provides all the circuitry needed for the RF stage in applications such as remote control; wireless security; and short-distance, low-speed data links. The AT1000 series from RF Monolithics, in a square 13×13×3-mm (0.5×0.5×0.125-in.) surface-mount package, delivers at least ­3 dBm (typically, 0 dBm) into a 50 ohm load. The module generates on/off keying modulation from a user-supplied digital stream and has just four connections: data input, RF output, 3V power (10 mA maximum), and ground. Each module costs $5 (1000).

RF Monolithics Inc, Dallas, TX. 1-972-233-2903, fax 1-972-387-8148.

IC uses speech recognition to defend and protect.

Sensory Inc's Voice Password speaker-identification IC operates in both a pin-configurable, stand-alone mode and under the control of a 4- or 8-bit microcontroller. Either way, the chip provides multiple-speaker, multiple-password detection using neural-network techniques. The IC features 64 kbytes of onboard ROM to store word and sound prompts, the ability to directly interface to 2 kbytes of serial EEPROM or SRAM (to store users' voice templates), and onboard speech synthesis and DTMF (dual-tone multiple-frequency) tone generation. The speaker-identification IC communicates with people and telecommunication equipment as well as generating appropriate control signals. A complete system requires the addition of a battery, a speaker, a microphone, external memory, a crystal, and an audio-input circuit. Voice Password IC costs $6 (50,000).

Sensory Inc, Sunnyvale, CA. 1-408-744-9000, ext 333, fax 1-408-744-1299.

68HC08 outperforms 68HC05

68HC08 µP architecture offers five-times higher performance than and object-code-compatibility with the 68HC05. Featuring an enhanced HC05 programming model, the 68HC08 has 78 new instructions, including eight additional addressing modes, a 16-bit index register and stack pointer, memory-to-memory data transfers, and BCD instructions. The bus interface runs at 8 MHz with a 5V supply. One of the first new products from the architecture, the 68HC708XL36, includes 36 kbytes of one-time-programmable ROM; 1 kbyte of RAM; a serial communications interface; a serial peripheral interface; a 16-bit, four-channel timer-interface module; three DMA channels; and a clock-generator module. The XL36 comes in a 56-pin SDIP or 64-pin QFP and sells for $13.25 (1000).

Motorola, Austin, TX. 1-800-765-7795, ext 858.

DSPs boost motor-control quality

Analog Devices has announced its version of a motor-control DSP, the ADMC330. Analog Devices based the ADMC330 on the company's ADSP-2171 core, which features three computational units, 2k words of program RAM, 1k word of data RAM, and 2k words of ROM preprogrammed with debugging software and motor-control functions. The device also features two serial ports; an interval timer; a seven-channel ADC; and a three-phase, center-based, 12-bit PWM generator. This PWM contains a high-frequency source that allows you to use transformer-coupled circuits to isolate high-voltage sources from a system's electronics. You can also configure the PWM to drive switch reluctance, ac induction, and permanent-magnet dc motors. The ADMC330 contains two auxiliary PWM timers for power-factor correction, setpoint control, and low-cost DAC capability. The device, which costs $10 (100,000), comes in a 68-pin PLCC package.

Analog Devices, Norwood, MA. 1-617-461-3881, www.analog.com.

Embedded 486 µP is PC/AT-compatible

The Elan SC400 µP is based on the 486SLE core with an 8-kbyte write-back cache to provide a minimal glue-logic implementation for PC/AT-compatible systems. PC/AT compatibility lets you exploit the range of available development support; run DOS and Windows; and use x86-compatible, real-time OSs. The SC400 operates from power supplies as low as 2.7V and integrates a power-management unit, five PLLs that generate all system clocks from a 32-kHz watch crystal, serial and parallel ports, a real-time clock, a dual PC-card controller, and a matrix keyboard controller. The SC400 also includes an LCD graphics controller that supports a unified-memory-architecture design. The device comes in a 292-pin ball-grid-array package and runs at 33 or 66 MHz. The 33- and 66-MHz versions sell for $39 and $44, respectively.

AMD, Austin, TX. 1-800-222-9323, www.amd.com.

LCDs carry onboard video controller

A medium-sized LCD module, the AND1391ST offers a resolution of 128×128 pixels and a fine dot pitch of 0.43×0.43 mm for clear, sharp images. Its square viewing area (62×62 mm) makes the AND1391ST useful for handheld equipment. A second LCD, the AND1741, provides a high-contrast, white-page display with a resolution of 240×128 pixels. Dot pitch is 0.47×0.47 mm, and a luminosity of 100 cd/m² and CCFL backlighting ensure easy viewing. Both units are equipped with a built-in LCD controller and character generator. The AND1391ST costs $78.26 (1000); the AND1741 starts at $154.57 (500).

Purdy Electronics Corp, Sunnyvale, CA. 1-408-523-8230.

8-bit flash microcontroller is SPI-programmable

The first in a series of flash-based microcontrollers, the AT89S8252 offers in-system programmability through a serial peripheral interface. The 8-bit microcontroller operates at 24 MHz and contains 8 kbytes of on-chip flash memory, plus 2 kbytes of on-chip EEPROM. Upward- socket-compatible with the industry-standard 8XC52 microcontroller, the AT89S8252 has 32 I/O lines, three 16-bit counter/timers, a full-duplex serial port, and on-chip oscillator and clock circuitry. Packaging options include 40-pin DIPs and 44-pin PLCC, PQFP, and TQFP versions. DIP prices start at $14 (1000).

Atmel Corp, San Jose, CA. 1-408-441-0311.

Power-management ICs serve battery-powered applications

An array of CMOS power-management ICs for battery-powered equipment in-cludes micropower dc/dc converters and undervoltage-sensing circuits. Offered in 3, 3.3, and 5V versions, the MC33463 VFM and MC33466 PWM switching voltage regulators have a quiescent bias current of 4 and 15 µA, respectively, and come in three-pin SOT-89 packages. Prices start at $0.85 (10,000). The undervoltage-sensing ICs have threshold voltages of 0.9, 2, 2.7, 3, and 4.5V. The MC33464 series has a quiescent current of 0.8 µA and comes in SOT-23 and SOT-89 packages, and the MC33465 series adds a programmable time-delayed output, has a quiescent current of 1 µA, and comes in an SOT-23. Prices start at $0.34 (10,000).

Motorola Semiconductor Products Sector, Phoenix, AZ. 1-602-413-3615.

FET-input op amps deliver 0.00008% audio distortion

A single op amp with FET input and its companion dual device target audio, filtering, and instrumentation applications. The unity-gain-stable OPA134 and OPA2134 from Burr-Brown feature 8-MHz gain-bandwidth product, 20V/µsec slew rate, and 0.00008% THD plus noise at 1 kHz, along with input-voltage noise of 8 nV/square root (Hz). Unlike some FET-input op amps, these devices are free from phase inversion and overload difficulties. They operate from dual 2.5 through 18V supplies, and outputs can swing to within 1V of either rail. They are available in eight-lead DIP or SOIC packages and cost $0.87 for the single-channel OPA134 and $1.09 for the dual-channel OPA2134 (1000).

Burr-Brown Corp, Tucson, AZ. 1-800-548-6132, www.burr-brown.com.

USB microcontroller costs less than $1

A microcontroller for mouse, joystick, and game-pad applications uses a RISC CPU core optimized for USB operations and offer 2 or 4 kbytes of on-chip EPROM for program storage. The devices also provide a watchdog timer, 10 to 16 general-purpose I/O lines, programmable-current LED drivers, and 128 bytes of RAM. An internal frequency doubler allows the device to operate using a 6-MHz crystal, reducing EMI. The CY7C-63000 with 2 kbytes of EPROM and CY7C63001 with 4 kbytes of EPROM come in 20-pin packages with 10 I/O lines. The CY7C3100 and CY7C3101 come in 28-pin packages with 16 I/O lines. Devices are available for sampling now, with production scheduled for February. Parts cost less than $2 (10,000) and less than $1 in higher volumes.

Cypress Semiconductor, San Jose, CA. 1-408-943-2600.

Switching regulators reconcile
incompatible parameters to operate efficiently

A pair of dual synchronous step-down switching regulators operates over an input range of 3.5 to 36V with efficiencies as high as 95%. The adaptive power-output stages in the LTC1538-AUX and LTC1539 ICs allow constant frequency operation and high-efficiency performance to coexist. The outputs of the regulators selectively drive two N-channel MOSFETs, which are less expensive and have lower on-resistance than do P-channel devices, at frequencies as high as 400 kHz. This type of output stage delivers high efficiency over two decades of load current yet maintains constant frequency. You can synchronize the switching frequency to an external source via the internal PLL. An on-chip reference (1.19V, ±1%), combined with remote load sensing, provides tight regulation of output voltage. Each half of either IC can regulate different supply voltages. Other features include programmable "softstart" to ease supply sequencing, low-battery detection, and resistor-settable output-current limits. The two dual regulators are available in 28- and 36-lead SSOP packages. The LTC1538-AUX and LTC1539 cost $7 and $7.55, respectively (1000).

Linear Technology Corp, Milpitas, CA. 1-408-432-1900, www.linear.com.

New Pentiums sport MMX

Pentiums now include single-instruction-multiple-data (SIMD) multimedia-extension (MMX) instructions and can provide two to eight times better performance for certain applications than previous versions. The Pentiums have double the cache (32 kbytes) of previous versions, as well as other microarchitectural enhancements. These enhancements include improved decoding and instruction pairing to more efficiently use the dual pipeline as well as improved branch prediction. The Pentiums run much faster than the non-MMX versions for both standard code and applications that independent software vendors have rewritten to include support for the MMX instructions. The 166- and 200-MHz desktop versions cost $407 and $550 (1000), respectively. These devices are available in ceramic or PPGA packaging. The 150- and 166-MHz notebook versions cost $443 and $550 (1000), respectively. The notebook versions are available in tape-carrier packaging.

Intel Corp, Santa Clara, CA. 1-800-548-4725, www.intel.com.

Rugged handheld PC is Pentium-powered

Housed in an aluminum-alloy case with an attached shoulder strap, the Tek-Field-OEM industrial portable computer packs a 100-MHz Pentium processor and 6.4-in. touch-sensitive color display. The self-contained unit comes with four PCMCIA Type II slots, one PCMCIA/ATA-IDE removable hard drive or flash disk, and dual mouse controls. Four serial ports and two parallel ports enable docking, infrared data exchange, and GPS mapping. You can also configure the Tek-Field-OEM base as a 12-in. tablet computer, a belt-wearable computer with heads-up display, or an embedded mobile-computer base. The computer costs $5081 with 16 Mbytes of DRAM and a 340-Mbyte hard drive.

Teknor Industrial Computers Inc, Boisbriand, PQ, Canada. 1-514-437-5682.

386 ROM DOS PC fits into handheld enclosure

The KB-8 portable PC-in-a-box packs a 33-MHz 386 CPU, 2 Mbytes of DRAM, a 16-line×24-character LCD, a 53-key alphanumeric keypad, one serial port, and ROM DOS into an 8.8×5.5×1.6-in. plastic enclosure. Options include flash memory, a PCMCIA Type II port, an additional serial port, a parallel port, and a battery pack. The ability to run complex DOS programs at low power makes the KB-8 useful for a variety of applications, such as industrial control, data acquisition, and medical monitoring. Prices start at $449 (100).

Kila Systems, Boulder, CO. (303) 444-7737.

Low-power MOSFETs fit into SOT-223 packages

A family of n-channel enhancement-mode MOSFETs supplied in tiny SOT-223 packages withstands high-energy pulses under avalanche mode and is suitable for use in hard-disk drives, dc/dc converters, power supplies, and small-motor current-sensing circuits. Initial members include the $0.38 (10,000) STN2N06, which has a maximum drain-to-source voltage of 60V and a maximum on-resistance of 0.25 ohms at 25ºC; the low-threshold, $0.45 STN2N10L (100V and 0.5 ohms); the $0.45 STN3N06 (60V and 0.15 ohms); and the $0.50 STN1N20 (200V and 1.5 ohms).

SGS-Thomson Microelectronics, Lincoln, MA. 1-617-259-0300.

Next-generation IGBTs improve efficiency

Used as drop-in replacements for older devices, Gen 4 IGBTs provide a 20 to 40% performance improvement over Gen 3 devices, with reductions in both switching losses and V_CE(on). The 600V IGBTs include the IRG4BC40U (TO-220), IRG4PC40U (TO-247), and IRG4PC40UD (TO-247) for switching power applications ranging from 20 to 75 kHz. A more efficient manufacturing process and improved yields shorten leadtimes to just two weeks for both Gen 4 IGBTs and Gen 5 HEXFETs. Gen 4 prices start at $2.48 (50,000).

International Rectifier Corp, El Segundo, CA. 1-310-322-3331.

32-bit microcontroller processes CAN protocol

The 68376 is the first device in the TouCAN series, a line of microcontrollers with an integrated controller-area-network (CAN) interface module. Based on a 32-bit CPU32 core, the 68376 performs complete protocol processing for CAN networks in automotive and industrial control applications. The device carries 8 kbytes of mask ROM, 4 kbytes of standby SRAM, a time-processor unit, a configurable timer module, a 10-bit ADC, a system-integration module, and an enhanced serial-communications interface. Housed in a 160-pin QFP, the 68376 costs $27.16 (10,000).

Motorola Microcontroller Technologies Group, Austin, TX. 1-512-328-2268.

Software generates Java code from state charts

BetterState Pro Version 4.0 now generates single-threaded and multithreaded Java source code from state charts and Petri nets. You can automatically port the generated Java class to and from C++ without changing the diagrammatic representation. Existing BetterState designs made for C++ applications can now generate Java code with little or no modification. The PC-based design tool costs $625 to $995.

R-Active Concepts Inc, Cupertino, CA. 1-408-252-2808.

mC derivatives expand 8-bit family

Two new members join the 68HC11 8-bit microcontroller series: the 68HC-11EA9 aims at automotive and communications applications, and the 68HC11KW1 targets factory-automation and industrial-control products requiring expanded memory. The EA9 includes a power-saving PLL circuit, 12 kbytes of ROM, 512 bytes of RAM, and 512 bytes of EEPROM. The KW1 packs 768 bytes of RAM and 640 bytes of EE-PROM, along with three independent 16-bit timers. Housed in a 52-pin PLCC, the EA9 costs $6.79 (10,000). The KW1 comes in a 100-pin TQFP and costs $11.48 (10,000).

Motorola Microcontroller Technologies Group, Austin, TX. 1-512-328-2268, ext 958.

Package creates Windows NT device drivers

WinDK lets you produce reliable device drivers for Windows NT 4.0 and 3.51 on Intel, DEC Alpha, MIPS, and PowerPC platforms. The kit supplies a large set of sample device drivers, along with the WinDK Class Libraries and reference documentation. WinDK adheres to the Microsoft NT DDK and Microsoft Developers Network guidelines for the NT driver model and supports kernel-mode driver development. The driver kit, which requires Visual C++ V4.X, costs $795.

BlueWater Systems, Edmonds, WA. 1-206-771-3610.

Transceiver IC for RS-485 shields against transients

To protect against the effects of overvoltage on bus pins, Texas Instruments' single-channel SN75LBC184 transceiver targets applications requiring RS-485 multidrop differential signals with high electrical noise, such as industrial control, alarm systems, and point-of-sale terminals. It integrates transient-voltage protection as high as 400W peak (typical), eliminating the need for external clamping diodes. The IC meets the CEI IEC 1000-4-5 transient specification defining overvoltage magnitude, duration, and waveshape. The transceiver also features controlled driver slew rates, allowing you to achieve low-error transmission over both long unterminated cable runs and backbone-cable stubs. Maximum data rate is 250 kbps over unshielded twisted-pair or similar balanced cables. The 5V IC offers open-circuit fail-safe mode, thermal shutdown, power-cycling glitch protection, and hysteresis. The SN75LBC184 interface transceiver for 0 to 70ºC operation comes in an industry-standard "176'' footprint, eight-lead DIP, or SOIC and costs $2.44 (1000); a ­40 to +85° version, the SN65LBC184, costs $2.72.

Texas Instruments Inc, Dallas, TX. 1-800-477-8924, ext 4500, www.ti.com.

USB hub ICs provide plug-and-play connections for PCs

The first two members of a family of Universal Serial Bus (USB) interface chips, the TUSB2070 seven-port hub device and the TUSB2040 four-port hub chip, simplify I/O connectivity for PCs. The hub devices provide USB connection ports for linking the PC to peripheral devices, such as modems, printers, keyboards, and mice, or to another USB hub if additional peripherals are needed. The TUSB2070 costs $5, and the TUSB2040 costs $4.10 (1000).

Texas Instruments Inc, Denver, CO. 1-800-477-8924, ext 5504.

Integrated supervisory IC cuts design time, board space

The TC70 and TC71 from Telcom Semiconductor incorporate the supervisory functions for a processor-based system into an eight-pin SOIC or DIP. The devices include a power-supply monitor, a watchdog timer, an external reset override, a threshold detector, and a battery-backup controller. Both ICs generate a power-on reset and monitor unstable processor operation, which may occur from power-supply brown-out. You can "wire-OR" their outputs to a manual switch or an electronic signal to reset the processor; the ICs also integrate contact-closure debounce. The two ICs are nearly identical but for one slight difference. The TC70 has a watchdog-disable pin, which eases prototyping and in-circuit emulation by deactivating the watchdog function. The TC71 has a power-fail output indication to act as a voltage monitor or low-battery indicator. Either 5V IC costs $1.57 (5000).

Telcom Semiconductor Inc, Mountain View, CA. 1-415-968-9241, fax 1-415-967-1590.

Video/graphics multiplexer uses analog color key

Allowing video and graphics to appear on the same display, the CH8439 multiplexer works with display resolutions to 1280×1024 pixels and 16.7 million colors. The IC accepts full-bandwidth analog RGB graphics and controls the mixing of digital video inputs using a programmable analog color key, while limiting graphics bleedthrough to less than 1 pixel. Housed in a 64-pin PQFP, the multiplexer uses a serial programming interface for video-attribute control. The CH8439 costs $9.75 (1000).

Chrontel Inc, San Jose, CA. 1-408-383-9328.

Dual-axis accelerometer has on-chip signal conditioning

Consuming one-fifth the power of its predecessors, the ADXL250 dual-axis ±50g accelerometer integrates signal conditioning on one IC. The device, which also comes in a single-axis version (ADXL150), provides a typical SNR of 74 dB at 100 Hz. Drift is reduced to 0.4g over the industrial-temperature range, representing a 10-times improvement over the ADXL50. Power consumption is only 1.8 mA/axis. Both versions come in surface-mount 14-pin Cerpaks. The ADXL150 and ADXL250 cost $12.45 and $19.95, respectively (100).

Analog Devices Inc, Wilmington, MA. 1-617-937-1428.

Genlock IC produces waveforms to digitize video

The ML6430 genlocking sync generator from Micro Linear takes the analog waveform and produces timing pulses for clamping, decoding, blanking, and video processing. It accommodates glitches and variations due to VCR head-switching, missing sync pulses, freeze frames, tape dropouts, and high-speed playback. The IC provides high noise immunity and is relatively insensitive to varying signal amplitudes, overmodulated color carriers, and signal glitches. Internal PLLs and signal-handling algorithms result in short-term, locked clock-timing jitter lower than 200 psec rms, and locked line-to-line jitter lower than 900 psec. You can select standard or nonstandard clock frequencies, as well as many other operating options, via pin selection or serial-control bus. The genlock IC provides a synchronized clock to trigger an audio digitizer at 48, 44.1, or 32 kHz and supports a free-running mode to ease creation of analog video output, such as those that MPEG decoders require. The 5V, 32-pin TQFP costs $15 (1000).

Micro Linear Corp, San Jose, CA. 1-408-433-5200, www.microlinear.com.

Chip bridges USB to parallel port

Lucent Technologies has provided designers a shortcut to designing USB peripherals. The USS-720 device acts as a bridge between the USB and an IEEE-1284 parallel port. You can use it to quickly adapt to the USB any existing products that offer a parallel port. You can also build the device into an external adapter that lets a user connect parallel peripherals to the USB. The USS-720 will be in production by the second quarter of this year. Baseline software drivers for Windows are under development at Lucent and SystemSoft (Natick, MA).

Lucent Technologies, Allentown, PA. 1-800-372-2447.

8-bit, 200M-sample/sec A/D converter avoids being flashy

The AD9054 from Analog Devices uses the company's proprietary MagAmp architecture to provide high-speed-per-bit conversion, with just one comparator per bit supported by a resident quantizer stage. In the final implementation, this 8-bit converter uses 19 comparators compared with 255 for a conventional flash design; the reduced number of comparators also simplifies and improves the input stage design. Total power dissipation for this 200M-sample/sec converter is less than 500 mW with a 5V supply. The A/D converter has a 380-MHz, full-power, ­3-dB bandwidth and includes an integrated track/hold amplifier and onboard reference. Its output data stream is available either as a single 8-bit parallel word or as two demultiplexed, interleaved 8-bit words at one-half the conversion clock rate. The 44-lead TQFP device costs $48 (100); a 135M-sample/sec version costs $28.

Analog Devices Inc, Norwood, MA. 1-617-937-1428, www.analog.com.

Tiny-op-amp family offers 80- to 350-MHz bandwidths

The CLC450 through CLC453 op amp/buffers from National Semiconductor Corp/Comlinear Product Group feature combinations of bandwidth, slew rate, and dissipation and operate from unipolar or bipolar 5V supplies. The devices target applications such as driving video lines, high-speed modem interface, broadband communications, and driving digital video A/D or D/A converters. For example, the CLC452 has a bandwidth of 130 MHz at gain of 2 with a 5V supply and dissipates 15 mW; with ±5V supplies, its bandwidth is 160 MHz, and dissipation is 30 mW. Slew rate is 400V/µsec, and second- and third-order distortion figures are ­78 and ­85 dBc, respectively. All devices in the family sink or source as much as 130 mA with dual supplies and 100 mA with a single supply, driving a 100 ohm load to within 1.2V of the supply rails. Prices begin at $1.39 (1000).

National Semiconductor Corp/Comlinear Product Group, Fort Collins, CO. 1-800-272-9959, www.national.com.

16-bit DAC squeezes into eight-pin SOIC

Maxim's MAX541 packs a 16-bit DAC designed for industrial and instrumentation applications into a space-saving SOIC. The three-wire serial-input (SPI, QSPI, and Microwire compatible) unbuffered voltage-out device requires an external reference (typically 2.5V) and provides ±1-LSB integral- and differential-nonlinearity specifications over temperature. Output span for the DAC, which consumes 1.5 mW at 5V, is 0V to V_REF. The MAX541 can drive a 60-kiloohm load and settles to 1/2 LSB in 1 µsec with a 10-pF load. The MAX541 has Schmitt triggers on its digital inputs to ease interfacing to relatively slow-transitioning optocouplers. An internal reset circuit sets the output to 0V at power-on. If you need a bipolar output swinging ±V_REF, you can use its larger sibling, the MAX542, which incorporates matched scaling resistors for use with an external precision op amp; the MAX542 also has provision for Kelvin sensing to increase output precision. The MAX-541 in eight-pin SOICs or DIPs cost $9.95 (1000).

Maxim Integrated Products, Sunnyvale, CA. 1-408-737-7600, www.maxim-ic.com.

Sensor detects carbon monoxide

The first in a series of chemical gas sensors, the Senseon MGS1100 carbon-monoxide device, uses an embedded heater layer to raise the temperature of its metal-oxide film to be sensitive to the target gas, and a micromachined silicon diaphragm reduces power consumption. The sensor, which supports current standards for residential CO detectors, comes with a stainless-steel mesh and an active charcoal filter for protection against damaging elements and to selectively screen "noise" gases. The MGS1100 costs $10 (low volumes).

Motorola Semiconductor Products Sector, Phoenix, AZ. 1-602-244-5064.

Video encoder/decoder handles NTSC and PAL signals

The new NTSC/PAL video chip set from Harris Semiconductor includes the HMP8112 decoder and HMP8156 encoder ICs. The set targets applications such as frame-grabber boards, VCR-to-PC editing systems, teleconferencing systems, and digital-video-disk players. The decoder offers several innovations, including a comb filter that, relative to bandpass or chromatap filters, optimizes luminance/color (Y/C) separation without losing vertical detail. Moreover, an integrated sample-rate converter allows the decoder to use any available clock, and a digital PLL ensures steady images even in low-cost, PC-based, image-editing applications. The HMP8112 costs $13.95 (10,000)--about half the price of other video decoders with comb filters. The encoder accepts data in RGB or YCrCb format and outputs either an NTSC or a PAL signal. It costs $8.95 (10,000), and both ICs are available now.

Harris Semiconductor, Melbourne, FL. 1-800-442-7747.

Low-cost digital thermometer tells you when to cool down

The less-than-$1.25 (10,000) DS1720 Econo-digital thermometer and thermostat has three user-programmable thermal-alarm outputs: T_HIGH, T_LOW, and T_COM, which stay high after a device exceeds a high-temperature threshold until the temperature falls below a low threshold. The thermometer/thermostat measures temperatures from ­25 to +85ºC in 0.5º increments with an algorithm that uses the effect of temperature on current flow in silicon. The user-defined temperature thresholds are stored on-chip in nonvolatile memory and are programmed before insertion in the system. These threshold values, as well as the output temperatures once the thermometer is operational, are written to or read from a three-wire serial interface that conserves pins on the eight-pin SOIC. The device communicates temperature as a 9-bit value.

Dallas Semiconductor, Dallas, TX. 1-972-371-4000, fax 1-972-371-3715, www.dalsemi.com.

Current sensors isolate input from output voltage

Secured in their housings with epoxy resin, these Hall-effect linear current sensors detect dc or ac, and the linear output voltage tracks the sensed-current waveform. When sensing zero current, the output voltage is equal to one-half the supply voltage. Output voltage is isolated from the input. The VHELCS series comprises six rectangular, vertical-standing models that range in input from 4.5 to 10.5V dc. Typical supply current is 7 mA. Devices operate over a temperature range of ­40 to +125ºC and cost less than $16 (1000).

Engineered Components Co, San Luis Obispo, CA. 1-805-544-3800.

Trim your analog circuit via electrical programming

You can custom-trim an analog function to produce a desired current source, voltage source, or voltage-controlled resistor value--and thereby avoid trimming potentiometers or calibration circuitry and software--using electrically programmable analog devices (EPADs) from Advanced Linear Devices. The EPADs are CMOS FETs. They have adjustable threshold (bias) voltages that you set via a stored, nonvolatile charge; increasing the threshold voltage also corresponds to lowering the drain on current as a function of a given input bias current. You can set the threshold to 0.1-mV resolution over a 2000-mV range. Applications for these devices include adjustable filters, low-temperature-coefficient bias circuits, programmable-gain amplifiers, and sensor-interface circuits. You program each EPAD, the quad ALD1108E and the dual ALD1110E, outside your final system by plugging the device into a DOS/Windows PC-based programming adapter, or "in-system," using the specified application circuit and algorithm. Although you can only increase--not decrease--the threshold voltage (and you can reprogram the device to a higher value), you can use different circuit configurations to implement designs that need both raised and lowered channel voltages. In volume quantities, EPAD devices cost less than $1; the programmer base unit costs $498, and programming adapter modules cost $149 and $199, depending on type.

Advanced Linear Devices Inc, Sunnyvale, CA. 1-408-747-1155, www.aldinc.com.

Motherboards dig embedded applications

The MTX mother-board family is an embedded version of the industry-standard ATX motherboard. The MBX family is a small motherboard with PC/104+- and PCMCIA-expansion capability. The MTX family puts the PowerPC processor into a PC-motherboard form factor. The board offers standard PC-I/O capability, including PS/2 mouse and keyboard interfaces, EIDE disk controllers, and SVGA graphics, as well as PCI-expansion slots. An MTX board also includes two PMC-expansion sites; a 100-Mbit Ethernet port; flash memory; and a choice of AIX (Unix), VxWorks, pSOSystem, LynxOS, or OS-9 real-time operating systems. Use of the PowerPC as the core processor allows MTX motherboards to meet the production-lifetime needs of embedded applications. Motorola controls production of its CPUs, allowing it to target MTX boards for three- to seven-year production life. Prices start at $1200 for boards with the PowerPC 603e CPU. The MBX family provides a 5.75×8-in. CPU board with two expansion options. An MBX board can accept a PCMCIA-Type 3 card and a stack of as many as three PC/104+ cards. The first family member, the MBX 860, uses a PowerPC 860 CPU, Ethernet, EIDE, keyboard, and mouse interfaces, and substantial memory options. The card has 4 Mbytes of DRAM, 4 Mbytes of flash memory, and 32 kbytes of nonvolatile RAM. The card also has one 168-pin DIMM slot that can accept as much as 64 Mbytes of additional memory. The board offers additional communications protocols with the I²C serial bus, four 16-bit timers, and a time-slot assigner for time-division-multiplexed communications. Prices for the board start at $745. An entry-level version without PC/104+ expansion starts at $545.

Motorola Computer Group, Tempe, AZ. 1-602-438-3000, fax 1-602-438-3518.

PCI-to-CardBus controller nears 132-Mbyte/sec PCI limit

The PCI1250 CardBus-to-PCI controller from Texas Instruments uses a dual-pipeline, wraparound-buffer architecture to achieve a 130-Mbyte/sec speed, approaching the interface's theoretical limit of 132 Mbytes/sec. The device has two ports for CardBus interfaces; each port can transmit or receive at the same time as the other port. This approach allows for two applications, such as high-speed networking and video processing, to run simultaneously. All parts in the series support Microsoft's PC 97 Advanced Configuration Power Interface (ACPI) for complete systems. The PCI1250 allows Windows to power down the controller while not in use and shut down socket power when a card is not inserted. The device functions in either 3.3 or 5V systems. The PCI1250 provides 12 programmable multifunction pins for interrupt signals, LED, or general-purpose I/O. The device also integrates zoomed-video buffers that support both slots. The second device in the family, the PCI1220, provides the same performance as the PCI1250 but lacks the integrated zoom-video buffers and has only eight programmable multifunction pins. It will be available in the same 208-pin TQFP as TI's previous CardBus controller. The PCI1250 is available in a 256-pin BGA and costs $16.52 (100,000). The PCI1220 will be available in the second quarter of this year for $14.24 (100,000).

Texas Instruments, Dallas, TX. 1-800-477-8924, ext 4500.

IC builds isolated bridge between
telephone line, electronics

The ITC135P from CP Clare incorporates a Form A solid-state relay comprising optically coupled MOSFETs for use as a 2-mW hook switch, a half-wave bridge rectifier, a Darlington transistor, an optocoupler that functions as a ring or loop-current detector, and transient-protection zener diodes. Applications include data/fax modems, voice circuits, computer-telephony interfaces, PCMCIA modems, and cable modems having a telephone connection. The FCC Part 68-compatible, 16-pin SOIC saves about 60% of board space compared with conventional implementations of the same functions. Its internal LED requires 5 mA to operate, and the IC can dissipate as much as 1W, accept loads as high as 350V, and conduct continuous loads as high as 120 mA. R_DSON is 15 ohms. With 350V blocking-voltage capability and as much as 3750V-rms I/O isolation, the ITC135P has unidirectional signal coupling; the otherwise-identical ITC137P has bidirectional coupling. The devices cost $4.36 each (10,000).

CP Clare Corp, Beverly, MA. 1-508-524-6700, www.cpclare.com.

PWM switches form core of simple supplies for 6 to 150W needs

The TOPSwitch-II family from Power Integrations puts a PWM controller, 700V power MOSFET, and supporting discrete devices into a three-terminal device. This device forms the core of a compact, 80 to 90%-efficient supply for desktop PCs, portable device chargers, and multimedia systems and peripherals. Family-member capacities span devices from 6W for the TOP-221Y, which costs $0.98 (10,000), to 150W for the TOP-227Y, which costs $2.24 (10,000). You can use the TOP-227Y to implement buck-, boost-, flyback-, or forward-topology supplies with either primary-side or optoisolator feedback. The switches incorporate autorestart, current limiting, and latching thermal shutdown. The devices that supply as much as 30W come in low-cost, eight-pin, plastic DIPs, which require no heat sinking; all members are also available in three-pin TO-220 packages. Reference designs and detailed application information are also available.

Power Integrations Inc, Sunnyvale, CA. 1-408-523-9200, www.powerint.com.

IC collapses speakerphone to one device

You can build a speakerphone using the Motorola MC33215 IC, dual-tone multiple-frequency (DTMF) dialer and ringer ICs, plus some passive components. To minimize feedback and howling, this telephone-line interface and speaker IC includes a half-duplex controller that monitors both transmit and receive channels and reduces the gain by 40 to 52 dB (set by the phone designer) in the channel with the lower gain. The phone-line-powered IC, in a 42-pin DIP or 52-pin QFP, requires 4-mA line current and lets you use approximately 90% of the loop current for the internal speaker amplifier. The IC lets you select ac- and dc-parameter operating points, such as set impedance, as well as switching depth from one mode to the other. It includes separate supplies for the handset and base microphones, and you can power and use the loudspeaker amplifier separately from the rest of the phone. Internal circuitry manages a smooth switchover from handset to speakerphone operation, as well as including ac- and dc-line termination, two- to four-wire conversion, and line-length automatic gain control. The IC costs $2.55 (10,000).

Motorola Semiconductor Products Sector, Phoenix, AZ. 1-602-413-3615, www.mot.com/sps.

Processor supports 57 MMX instructions

The Pentium II, otherwise known as Klamath or P2, is a 266-MHz PentiumPro with support for the 57 multimedia-extension (MMX) instructions and 16-kbyte, level-1 instruction and data caches. Similar to the PentiumPro, P2 supports out-of-order execution; speculative execution; register renaming; the backside level-2 cache bus; and the PentiumPro's pipelined, multiple-transaction bus structure. Also, Pentium II can still use Intel's 440 FX chip set. Unlike PentiumPro, P2 operates with industry-standard pipeline-burst SRAMs that run at half the speed of the processor core. P2 features improved 16-bit performance and a flash reset for the shared floating-point/MMX registers. Although the Pentium requires as many as 50 clock cycles to reset the shared registers when switching from MMX to floating-point mode, P2 requires fewer than 10 clock cycles. A single-edge-contact (SEC) cartridge replaces the standard PGA. The SEC cartridge contains the Pentium II and a 512-kbyte, level-2 cache surface mounted to a substrate and enclosed in a plastic and metal cartridge. Similar to PCI add-in cards, the SEC cartridge plugs into what Intel calls "Slot 1'' on a PC motherboard. The 233- and 266-MHz versions sell for $636 and $775, respectively (1000).

Intel Literature Center, Mount Prospect, IL. 1-800-548-4725, www.intel.com.

Op amp outslews monolithic competitors

The current-feedback AD-8009 op amp from Analog Devices features a 5500V/µsec slew rate--twice that of available monolithic devices--and rise/fall times of 725 psec for a 4V step. The AD8009 offers 1-GHz small-signal bandwidth (unity gain) and 700 MHz (gain of 2), and spurious-free dynamic-range figures are 74 dBc at 5 MHz, 53 dBc at 70 MHz, and 44 dBc at 150 MHz. The device settles to 0.1% of full scale within 10 nsec. Operating from ±5V supplies, the op amp drives at least 150 mA into a 10 ohm load; it can also drive four "back-terminated" video loads with less than 0.03% differential gain and 0.03º differential phase errors. The AD8009 costs $2.99 (1000).

Analog Devices Inc, Norwood, MA. 1-617-937-1428, www.analog.com.

Wireless-LAN module yields
maximum performance in micro package

Proxim has developed the 2.4-GHz, 1.6-Mbps RangeLAN2 6330, a frequency-hopping, spread-spectrum module that measures 1.65×2.65×0.23 in. (42×67×5.8 mm) thick, about two-thirds the size of a standard business card and half the size of a standard PCMCIA card. The 0.7-oz/20g module, which includes an ISA interface to simplify integration, is compatible with Proxim's RangeLAN2 PC Card and ISA adapters, access points, and design-in modules, and it complies with the Wireless LAN Interoperability Forum specifications. It supports 15 noninterfering, colocated channels, so that you can operate as many as 15 networks in one location. With its 20-dBm output with 2-dBi antenna gain, the typical 6330 range is 1000 ft (approximately 300m). Because multipath and fading can be problems with low-power mobile units, the 6330 supports antenna diversity, allowing you to control an external switch and thus select between two antennas. Typical receiving sensitivity is ­85 dBm with BFSK modulation and ­77 dBm with 4FSK (four-state FSK) modulation. The card operates from a 5V supply and consumes 300 and 150 mA in transmitting and receiving modes, respectively. It also offers lower than 10-mA sleep and doze modes. A developer's kit and design guide include hardware, software, support, and documentation for a two-node network, along with DOS and Windows drivers, driver tools (portable C source code) for non-DOS applications, and other utilities. The RangeLAN2 6330 costs less than $350, depending on OEM volume, and the developer's kit costs $4995.

Proxim Inc, Mountain View, CA. 1-415-960-1630, www.proxim.com.

TSOP clip enables probing of fine-pitch IC packages

A new low-profile TSOP clip from Emulation Technology allows the spacing between TSOPs to be as small as 0.03 in. yet offers a variety of ways to get good-sized probes onto the IC leads. The heart of the clip is a patented element that the company calls a "directionally conductive elastomeric connector." In fact, the elastomeric part is not conductive at all. Wrapped around an elastomeric insulator is a thin layer of Kapton on which parallel conductors are printed. These conductors contact the IC leads. You solder the TSOP ICs to your board in the normal way and snap the clips onto the chips. The clip extends the IC leads to test points on rigid or flexible circuit boards of several configurations. Your probes or connectors contact these boards. You can replace the "conductive-elastomeric" subassemblies should they exhibit wear after a large number of insertion/withdrawal cycles. Prices begin at $450.

Emulation Technology Inc, Santa Clara, CA. 1-408-982-0660, fax 1-408-982-0664, www.emulation.com.

Universal tuner IC modulates,
translates signals to any TV standard

Siemens' TDA606XS IC, a software-controlled tuner and modulator, combines video and audio signals and translates them to frequencies and formats compatible with NTSC, PAL, and SECAM standards. Applications include modulator boxes, videorecorders, games, satellite receivers, and cable-head-end and set-top boxes. The single-chip design includes a gain-adjustable video amplifier; an AM video modulator based on a double-balanced mixer; a balanced carrier oscillator; and a sound modulator that is selectable at 4.5, 5.5, 6, and 6.5 MHz for FM and 6.5 MHz for AM. When a 4-MHz crystal source drives the modulator oscillator, you can set its frequency from 30 to 950 MHz in 250-kHz increments by controlling the onboard digital PLL that you address via the device's I²C bus interface. Internal registers allow you to set other operating parameters and to read flags, such as those indicating PLL lock or a signal's exceeding the clipping level. The 5V, 28-lead TSSOP device costs $2.58 (10,000).

Siemens Components Inc, Cupertino, CA. 1-408-777-4500, www.sci.siemens.com.

RFID tags shrink and gain flexibility

Except for the tiny bulge of an embedded IC, the Interactive Identification (I²) RF-identification (RFID) tag from SCS Corp looks and feels like a short strip of flexible plastic tape. Each 2.4×0.4×0.004-in. tag receives and transmits data at 2.4 GHz without a battery, using on-chip circuitry to convert and store energy from received signals' carrier waves. Read and write distances are nominally a foot or so, but they can be considerably greater, depending on the power transmitted by the scanner unit that reads and writes to the tags. The I² tags owe their size to their 2.4-GHz operating frequency, which allows printing an antenna on each flexible tag. In contrast, RFID tags that operate at lower frequencies require embedded coil antennas. For reliable operation, the I² technology uses frequency-hopping spread-spectrum techniques similar to those of wireless LANs. You need an FCC license to use some ac-operated scanners, but you can use low-power, handheld scanners without a license. Both types of scanners are available from SCS. SCS envisions that the tags will find use in baggage-handling, parcel-tracking, and uniform-rental applications. (The tags can be sewn into the seam of a garment and can withstand commercial laundering.) An I² tag costs $0.95 (100,000). A development kit, including a scanner, software, and 1000 tags, costs $4500.

SCS Corp, San Diego, CA. 1-619-485-9196, fax 1-619-485-0561.

Analog ICs end FPGA envy

The MPAA020 field-programmable analog array (FPAA) and its MPAA3DS development-system evaluation kit from Motorola give analog designers coveted versatility. The FPAA contains an array of 20 identical configurable analog blocks, arranged in a four×five-block matrix. Each block includes a switched-capacitor op amp, a comparator, capacitor arrays, CMOS switches, and static RAM. The SRAM data controls the switches that set static and dynamic capacitance values in the op-amp input and feedback paths. Using an MPAA block, you can build programmable gain stages, analog adders or subtracters, and first-order filters. You use multiple blocks to configure higher level functions, such as biquad filters, PLLs, or level detectors. Bandwidth is approximately 200 kHz, with integral and differential nonlinearity of less than 0.15 and 0.24 LSB, respectively. The development kit includes a PC interface and a CD-ROM with an interactive design tool for Windows, along with a library of macros for gain stages, a track-and-hold amplifier, a rectifier, and various filters. The board provides interface headers, so that you can monitor input and output signals, plus a breadboard area for additional circuitry. The MPAA020 analog array costs $50 in small quantities, and the development kit costs $1500.

Motorola Semiconductor Products Sector, Phoenix, AZ. 1-602-413-4034, www.mot.com/sps/general.

Parallel-port unit turns PC into 100M-sample/sec DSO

The two-channel, 30-MHz-bandwidth DSO-2102M from Link Instruments costs $599. The 9-oz, 7×3.5×1-in. (plus power supply) unit plugs into the PC's parallel port. The vendor supplies software to run the scope under Windows 3.1, Windows 95, and MS-DOS. The DSO takes 100M samples/sec/channel in real time via a separate flash ADC and 32k-sample acquisition memory for each channel. A similar unit, the DSO 2102S, costs $499 and lacks only the advanced triggering and waveform-analysis features. The DSO-2102M triggers not only on pulse width, but also on the nth occurrence of a pulse of a specified width. Moreover, you can set the scope to wait to trigger until after the occurrence of n waveform edges that meet the trigger specifications. The unit also measures 45 pulse parameters and performs pass/fail testing using 10 sets of pulse parameters or high/low limits. Finally, the unit calculates 32k-point FFTs. Although FFT capability is available on most of the competitive units, it is typically optional.

Link Instruments, Fairfield, NJ. 1-201-808-8990, fax 1-201-808-8786, www.linkinstruments.com.

IR transceivers for IrDA pack a lot into little space

Infrared transmission and IrDA (Infrared Data Association) standards let you build short-distance, medium-rate link capability into your PC, peripheral, personal digital assistant, cellular phone, or pager. This ability can eliminate the need for an electromechanical connector and its requisite enclosure opening, which can diminish your system's integrity. Temic Semiconductors' TFDU4100 IR transceiver supports 115.2-kbps data rates at distances as long as 3m; the similar TFDU6100 supports 4-Mbps data rates at 1m. Both transceivers integrate the optical components along with the mixed-signal control IC--which in-cludes receiver automatic gain control, a transmitting driver, a receiving amplifier, and a comparator--in a 4-mm-high, 9.7×4.7-mm package. You can use the same surface-mount device for either side- or top-view pc-board applications. The slower IrDA transceiver requires 3V at 1.5 mA for receiving, or 5V/2.5 mA, and operates as low as 2.4V for less-than-standard distances. Maximum transmit current is 0.5A; a typical transmission duty cycle is about 20%. The faster transceiver uses a 4.5 to 5.5V supply with a typical receiving supply current of 5 mA. Both the $2.90 (1000) TFDU4100 and the $5.40 (1000) TFDU6100 also support a standby mode with currents of 500 nA and 100 µA, respectively.

Temic Semi-conductors, Santa Clara, CA. 1-408-567-8220, www.temic.com.

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