Design Feature: August 15, 1996

When the going gets tough...
products for harsh environments

The electronic equipment you design often takes some rough treatment. It will most likely, at one time or another, get bumped, dropped, and exposed to dust and contaminants. Unless that equipment is very lucky, it will probably have to occasionally endure freezing temperatures, blistering heat, and high humidity. And that's if it's being used in benign environments. Heaven help the system that has to work in harsh environments.

Many electronic components are available in "ruggedized" versions and in extended-temperature versions. Others aim solely at applications for harsh environments. In this special product section, we present a sampling of components you can use to design products that are sure to face some tough situations. We hope they make your design tasks a little easier.

Mil-Spec-equivalent notebook PC has full-sized AT slot.

The Pentium-based IN Lite Mil-Spec PC meets IEC standards that are equivalent to requirements of MIL-STD-810E, MIL-STD-1275(A), and MIL-STD-461D. For versatility, the PC has a full-length, full-height AT expansion slot and two PCMCIA slots. The PC has a magnesium case to guard against shock, vibration, and EMI/EMC conditions. Built-in dual power supplies automatically adapt to 115 and 220V (40 to 440 Hz) and 18 to 36V dc. Each PC can accept as much as 64 Mbytes of DRAM. Storage options include 800-Mbyte and 1.3-Gbyte EIDE disk drives, and display options include 9.4-in. STN, 10.4-in. TFT VGA, and 12.1-in. XVGA flat panels. Prices start at <$10,000. Kontron Elektronik, Newport Beach, CA. (800) 566-8766, fax (714) 851-3180.

http://www.kontron.com

DC/DC converters have wide temperature range.

The IMX7 family of 7W dc/dc converters operates from -25 to +71°C or from -40 to +85°C without derating. Inside each module, a custom-control circuit and a planar transformer, mounted on a conformally coated multilayer board, result in high efficiency over the entire input-voltage range. The devices provide 1500V dc isolation, IEC 801 input transient-voltage protection, and radiated EMI below level B of EN550ww. It costs $52.20 (1000). Melcher Inc, Chelmsford, MA. (800) 828-9712, fax (508) 256-4642.

Vehicle-mounted printer takes rough treatment.

The vendor's 8i 80-column printer provides the extreme ruggedness required for use in vehicles. It comes in in blow-molded polyetheline for resistance to heat, cold, and ultraviolet rays. In addition, the print mechanism and electronic components are encased in steel for structural protection. Sealed switches and connectors keep out the elements. A straight-through paper-feeding meth-od allows the printer and its paper stack to fit in a self-contained unit that measures 4.5×14.25×12 in. A built-in infrared port simplifies communication with the printer. The printer can operate from a cigarette lighter or wall adapter and includes a shoulder bag for portability. It costs $889. O'Neil Product Development Inc, Irvine, CA. (714) 458-1234, fax (714) 458-0708.

SRAM chips and modules meet DESC qualifications.

A 512k×8-bit SRAM chip and a 512k×32-bit SRAM multichip module meet DESC qualifications. Both are available in military, industrial, and commercial temperature ranges with a wide variety of access times. The WMS512K8-XXX chip comes in a 32-pin DIP, a 32-lead CSOJ, a 36-lead SOJ, or a flat pack. The WS512K32N-XXX module comes in three package types: a 66-pin, 1.385×1.385-in.-sq ceramic HIP; a 68-lead, 1.56×1.56-in.-sq low-profile CQFP(G4T); or a 68-lead, 0.88×0.88-in.-sq CQFP/J(G2). You can configure the modules as 1M×16 or 2M×8. The 4-Mbit military-version chips cost <$300 (100), and 16-Mbit military-version modules cost <$1200 (100). White Microelectronics, Phoenix, AZ. (602) 437-1520, fax (602) 437-9120.

OEM kit provides industrial keyboard and pointing device.

The HulaBook OEM kit includes an industrial silicone notebook-sized 101-key keyboard, a small-footprint embedded pointing device, a controller board, and cable. The pointing device, called the microHulaPoint, is available in two versions: 2×2 or 1.5×3.5 in. The kit is available in XT-, AT-, and PS/2-compatible models. Customized keypad colors, legends, keyboard controllers, and enclosures are also available. Each model costs $349 for a single package, or $194 (500). Texas Industrial Peripherals, Austin, TX. (512) 837-0283, fax (512) 837-0207.

http://www.ikey.com

Remote ADC comes in NEMA4 enclosure.

Model RAD128, an eight-channel, A/D converter/controller provides an optically isolated serial interface to any host computer that has an RS-485 port. The unit comes in a stackable NEMA4 enclosure, and it can function individually or with as many as eight of the manufacturer's 16-channel IM-16P analog-input multiplexer/conditioners to accept as many as 128 single-ended or differential analog inputs. You can program its eight lines either as input or output. Input ranges are ±10V, ±5V, 0 to 10V, and 0 to 5V. The converter costs $385. Acces I/O Products, San Diego, CA. (619) 693-9005, fax (619) 578-9711.

MXbus modules serve mission-critical applications.

The MX1553-2 MXbus module allows use of two single-board military computers in one VME slot. It provides two dual-redundant MIL-STD-1553B interfaces, plus an 8-bit TTL parallel I/O port. It works with latest generation single-board computers that support the MXbus for expansion of military systems. The expansion module is available in five air- and conduction-cooled models for development-grade, severe-environment, and mission-critical applications. The module supports bus-controller, remote-terminal, and monitor-terminal modes on each channel. For applications that do not need or must not have bus-controller capability, the module is available with remote-terminal mode only. Prices start at $3800. Radstone Technology Corp, Montvale, NJ. (800) 368-2738, fax (201) 391-2899.

Industrial mouse has NEMA 4X rating.

The Industrial Mouse, available in versions for handheld use and for mounting in a panel, is NEMA 4X rated for harsh industrial environments. Both offer a full-travel, inductive joystick that is either pencil style for fine control or thumb-activated for coarse selection. The units require no calibration or adjustment, and, with no thermal drift, they eliminate zero-offset variation. The products operate from 0 to 70°C, and boot and gasket seals provide resistance to water, oil, solvents, dirt, and chemicals. A handheld unit costs $299, and a panel-mount version costs $289. CTI Electronics Corp, Stratford, CT. (203) 386-9779, fax (203) 378-4986.

VCXOs meet specs from -40 to +85°C.

Three voltage-controlled crystal oscillators—M6021, M6022, and M6-023—provide PLLs with guaranteed respective frequency-capture ranges of ±75, ±150, and ±300 ppm from -40 to +85°C. The VCXOs are available for center frequencies from 1 to 175 MHz. Control voltage can vary at rates to 20 kHz and still allow synchronism with PLL input-frequency variations. Current draw ranges from 13 to 19 mA, depending on operating frequency. Phase jitter is <100 psec. The VCXOs come in DIPs and are available in ECL and HCMOS. The oscillators cost $13.50 (1000). MF Electronics Corp, New Rochelle, NY. (914) 576-6570, fax (914) 576-6204.

Sealed PC tolerates harsh environments.

The 5200 Mini-PC, available in monochrome and color versions, provides a compact profile for harsh-environment applications. It has a NEMA 4/4X sealed front panel and a sealed 54-key keypad with 32 function keys. Its modular design provides easy access to internal components, connectors, and screen bulbs. The monochrome model withstands operating temperatures from 0 to 45°C; the color version works from 0 to 50°C. The 5200 uses a PC-compatible BIOS to run applications under MS-DOS. Expansion features include a PC Card (PCMCIA) interface, a PC/104 site, or a PC/XT bus expansion slot. The unit also has two isolated serial ports, configurable either as RS-232C or RS-485. Options include rotating and solid-state disk drives. Prices start at $2995. Xycom Inc, Saline, MI. (800) 289-9266 or (313) 429-4971.

Surface-mount shock sensor protects data.

The SMA-KS1 surface-mount shock sensor (accelerometer) provides data protection when designed into hard-disk drives or other rotating memory devices. When the device senses a shock, it produces a pulse that you can use to temporarily disable write-head electronics. Pulse output levels are proportional to acceleration, typically 1.85 mV/g, or 37 mV for a 20g shock. The sensor is a piezoelectric crystal that comes in a 2.8×6.4×1.5-mm package that weighs 0.14g. It operates on 5V over a range of -40 to +85°C. The SMA-KS1 costs $0.80 (100,000). Raltron Electronics Corp, Miami, FL. (305) 593-6033, fax (305) 594-3973.

Rugged PC enclosures reduce EMI/RFI emissions 50%.

The GIRSystem (Global Interference Reduction System) upgrade for the manufacturer's computer enclosures allow use of Pentium- and Alpha-based computers and reduces EMI/RFI emissions below FCC Class B and 1996 European requirements. A redesigned rear-chassis panel has copper-beryllium fingers that grip card guides along the sides to eliminate electrically noisy gaps. Beryllium gaskets, door grounding, and other grounding techniques further reduce noise. The upgrade is available for 12 enclosure models, including models for PCI, EISA, and ISA passive or active backplanes. Prices range from $899 to $1659. Industrial Computer Source, San Diego, CA. (800) 677-7329.

Rugged, illuminated keyboard brightens low-light situations.

You can use the LumineCKS series of illuminated keyboards for low-light environments in military and aviation control centers, process-control sites, and photographic processing labs. Its LED-backlit keys are individually addressable, allowing the keys' lights to turn on, off, or blink and, thus, serve as alarms or as highly visible conveyers of information to users. Each keyboard comes in a steel case, with additional protection provided by a polyester front sheet. Sealing meets NEMA 4 or NEMA 4X requirements, and the keyboards meet all applicable EMC/EMI requirements. The keyboards costs $919 each, with OEM discounts available. Computer Keyboard Systems, Santa Monica, CA. (310) 395-4639, fax (310) 393-6040.

Covers protect computers in dirty environments.

YezTech covers stay on a computer at all times, even when the computer is in use, to prevent dirt and debris from entering. Made of antistatic vinyl, the covers have removable filters and Velcro flaps, which allow access to disk drives. The covers come in sizes for many desktop and tower computers; accessory pockets for floppy disks, CD-ROMs, and documents are available. The covers cost <$60. Electronic Covers & Filter Inc, Minneapolis, MN. (612) 721-7845, fax (612) 721-5241.

Industrial workstation meets NEMA4 specs.

The Model NW4 workstation consists of an industrial PC and a large-screen CRT touch monitor mounted in a sealed, sheet-metal enclosure. The workstation is completely sealed when you choose an appropriate rear panel. Construction is of 14-gauge steel, with 11-gauge steel for the front panel. The workstation mounts on a shelf, a pedestal, or a pendant arm. It's available with 15-, 17-, and 20-in. monitors and a variety of processor, motherboard, and keyboard options. With 486-based PC and 15-in. monitor, prices start at $3985. Nortech Engineering Inc, East Walpole, MA. (508) 668-3490, fax (508) 668-3568.

ISA/PCI chassis mounts on bench or wall.

The Model 9040 chassis for embedded-computer systems mounts on either a bench or a wall and provides as many as four two-thirds-length ISA-card slots. A drive bay holds as many as two 3.5-in. disk drives, which can be individually shock-mounted for rugged applications. Chassis construction is of 16-gauge reinforced steel, with internal fans in both the chassis and 70W auto-sense switching power supply. The chassis costs $355. Micro Computer Specialists Inc, Vista, CA. (800) 347-6274, fax (619) 598-2450.

Batteries work from -55 to +100°C.

Eternacell TCL lithium-thionyl-chloride batteries self-discharge <1%/year and operate at temperatures from -55 to +1008C. They're available in standard cell sizes, including ½AA, AA, ²/₃A, A, C, and D. Depending on the packaging needed for an application, small cells typically cost $0.35/Whr; large cells can cost as little as $0.20/Whr. Power Conversion Inc, Elmwood Park, NJ. (800) 730-7733 or (201) 796-4800.

Rugged touchscreen fits 10.4-in. flat-panel displays.

The rugged Systems T6 adds infrared touchscreen capability to 10.4-in. VGA flat-panel displays. When installed with the gaskets provided, the T6 meets NEMA 4 and 12 (IP-65) requirements. Moisture, dust, contaminants, vibration, and heat from extreme operating conditions do not affect its performance. The operating temperature is 0 to 55°C. The complete system includes a sealed bezel filter, an IR touch array, a mounting frame, and a controller card. A clear filter is available for LCD and plasma displays; an amber filter works best with electroluminescent displays. Prices start at $695. Lucas Control Systems Products, Hayward, CA. (800) 376-1154, fax (510) 489-3500.

Rugged portable PC has 10 board slots.

The MegaPAC offers expansion of 10 full-sized add-in slots in a rugged, portable, Pentium-based PC. All the slots—six ISA, three PCI, and one ISA/PCI—accommodate full-sized cards. Slot power comes from a range of universal ac and dc power supplies with capacities from 200 to 350W. A suspension system protects the internal chassis from shock and vibration; a thermostatically controlled cooling system continuously adjusts three fans to keep internal temperatures within bounds. The MegaPAC includes a 10.4-in. color active-matrix TFT (VGA or SVGA) display, a fold-down keyboard with integral pointing device, memory to 128 Mbytes, disk drives with capacity to 9 Gbytes, and other options. Prices range from $6995 to $7495. Dolch Computer Systems, Fremont, CA. (510) 661-2220, fax (510) 490-8345.

Subminiature relays perform heavy-duty switching.

The R52 series of board-mountable relays performs heavy-duty switching over a temperature range of -30 to +85°C. The open-frame relays handle 40A of current with a coil voltage of 12V and come with either SPST-NO or SPDT contacts. The relays have dielectric strength of 750V rms between coil and contacts as well as between contacts of the same polarity. Relay weight is 0.63 oz. They cost $1.83 (1000). NTE Electronics Inc, Bloomfield, NJ. (800) 683-6837.

Pressure sensors have stainless-steel housing.

Pressure sensors in the 19C series have stainless-steel housings for use in harsh environments. The 28 products in the series come in seven pressure ranges from a low range of 0 to 15 psi to a high range of 0 to 500 psi. The sensors are laser-trimmed to a 100-mV (±1%) full-scale output. The zero-pressure offset is ±1 mV. The devices have temperature compensation to limit typical thermal shifts to ±1%/°C from 0 to 50°C. The devices operate from 0 to 50°C and from -20 to +105°C. Typical accuracy (combined linearity, hysteresis, and repeatability) is ±0.50% of full-scale output. Prices start at $40.25 (100). SenSym Inc, Milpitas, CA. (408) 954-1100, fax (408) 954-9458.

Differential I/O modules minimize noise effects.

Differential I/O IndustryPacks minimize the effects of electrical noise and drive long digital I/O lines near noisy equipment in commercial, industrial, and military applications. The EIA-422 (formerly RS-422) modules are credit-card-sized, plug-in mezzanine modules that are available for all major buses, including VME and PCI. Each module provides 24 EIA-422 I/O lines. As many as four modules can fit into a single VME or AT slot to provide as many as 96 lines. When using their DMA feature and operating at 8 MHz, the modules typically achieve 1.5-Mbyte/sec transfer rates. Prices start at $380. GreenSpring Computers, Menlo Park, CA. (415) 327-1200, fax (415) 327-3808.