Cleveland, OhioJoining the likes of Data Translation Corp, National Instruments, and others, test-and-measurement house Keithley Instruments is rolling out a new line of PC-compatible data-acquisition and control modules. Called the KUSB-3100 Series, they're based on USB (Universal Serial Bus).
Keithley's KUSB-3100 line is billed as an alternative to ISA bus and PCI bus data-acq cards, as well as PCMCIA data-acquisition PC Cards.
Series KUSB-3100 modules are multi-function devices that can be used for a range of applications. They can measure voltage, temperature, strain, and vibration, for example, and are capable of frequency, event counting, and timing applications, too.
Many Modules To Choose From
The KUSB-3100 Series product line-up consists of five different modules. A Model KUSB-3100, and a Model KUSB-3102 offer 12-bit resolution and sample rates of 40-ksamples/s and 100-ksamples/s, respectively. Model KUSB-3108 and KUSB-3116 modules pack 16-bit resolution and can sample at speeds to 50-ksamples/s and 500-ksamples/s, respectively.
These multi-function modules offer from eight to 16 analog input-channels, and up to four analog-output channels. They also include 16 to 33 digital I/O lines, and up to five counter/timer inputs.
The top-of-the-line module, the Model KUSB-3116, is USB 2.0-compliant, giving you USB's high-speed 480-Mbit/s data transfer rate. That bandwidth lets you perform multiple I/O operations simultaneously at throughput rates up to 500-kHz in each direction. That's quite akin to what you'd get in a PCI measurement system.
Thanks to USB, these compact data-acq modules are also plug-and-play capable, and quite portable. Using USB as an interface sidesteps dependence on PC motherboards, where slots for plug-in boards would be required.
What's more, you can install a KUSB-3100 module without the need to open your PC to add any plug-in boards. There's also no need to configure DIP switches or change IRQ (interrupt) settings.
You won't have to search for a device driver, nor reboot your system. Your PC will automatically identify the data-acq modules and then install the necessary software. What's more, Series KUSB-3100 modules can be installed or removed while your computer is running. Just plug in the device, use it, and unplug it when measurements are complete. There's no need to power-down the PC.
In use, you get USB 2.0 and USB 1.1 compatibility. Series KUSB-3100 products support USB's so-called full-speed data rates, for data acquisition sampling rates as high as 100-kHz.
Series KUSB-3100 modules can also be powered directly from a USB port using a supplied USB cable, or they can be powered from an external power source, such as Keithley's Model KUSB-3116.
Note however, that your USB port voltage must be between 4.75-V and 5.25-V (although the modules have been tested from 4.65-V to 5.5-V without any problems). In most cases the module will start down to 4.5V. However, you may encounter a problem with series switch impedance on some laptops. The KUSB-3100 Series modules will typically draw less than 400-mA of USB's 500-mA specification.
Low Noise, High Isolation
Being outside a PC's chassis, these modules also confer lower noise-sensitivity than plug-in boards. That can ensure more accurate measurements. Because USB cables are typically 1 meter to 5 meters long, I/O circuitry is located further away from electrically noisy motherboards and power supplies, and closer to the signals they will be measuring.
Most Series KUSB-3100 modules also provide a 500-V isolation barrier, protecting both the PC and the input device from damage caused by spikes, surges, or shorts. This protection also prevents the PC operating system from inadvertently shutting down, ensuring continuous operation.
Multi-Point Digital I/O
Keithley also offers a KUSB-3160 module that comprises a multi-point digital I/O system. This module has 96 digital lines that can be used for monitoring or control in high channel-count applications.
Signal connectivity is made through a variety of means including built-in screw terminals, BNC coaxial cable connections, DB-37 D-type connectors, or using mass termination connections. These built-in connectors eliminate the need for additional accessories, such as cables and screw-terminal panels that are typically required for ISA and PCI plug-in boards.
All KUSB-3100 Series modules come with a variety of software tools including Keithley's Quickstart applications. Also included are visual programming tools and drivers, and support for TestPoint and National Instruments's popular LabVIEW package.
You can also develop applications in VisualBASIC and Visual C++, using supplied ActiveX controls. Microsoft C developers can use a supplied SDK (software development kit) for writing applications for Windows 2000 or Windows XP operating system PCs.
Price and Availability
The Model KUSB-3100 module is priced at about $350. A Model KUSB-3102 goes for about $685. The Model KUSB-3108 is priced at about $1045, and the Model KUSB-3116 goes for under $2500.
The Model KUSB-3160 multi-point digital I/O system is priced at less than $700. All Series KUSB-3100 modules carry a three-year warranty.
Units will be available from stock as of April 2005.
For more information, and to view a short on-line product presentation, click here.
Or contact Keithley Instruments, Inc., 28775 Aurora Road, Cleveland, Ohio 44139-1891. Phone: 800-688-9951, or 440-248-0400. Fax: 440-248-6168. E-mail: firstname.lastname@example.org.
Be sure to visit Keithley's Web site to learn more about these modules and related products.