Multiplexer Modules offer RF switching to 2GHz and 3.5GHz.

Keithley Instruments, Inc. Mar 14, 2002

Press Release Summary:

Model 7711 and 7712 RF Switch Modules are designed for Model 2700 and 2750 Multimeter/Switch Systems. Both offer 50 Ohm, dual 1x4 multiplexer configuration with rear panel SMA connectors. Modules allow flexible signal routing, with either local control through 27xx mainframe's front panel or remote PC control over GPIB or RS-232 interface. Maximum signal level is 30Vrms or 60VDC (30VDC for 7712), 0.5A, up to 10W per channel and 20W per module.

Original Press Release:

Keithley Introduces Only DMM/Switch System With RF Switch Capability To 3.5GHZ

(Companion Product Launched As Low Cost, General Purpose 2GHz Switch Module)

CLEVELAND-February 28, 2002-Keithley Instruments, Inc. (NYSE: KEI) has introduced two RF multiplexer modules for its popular Model 2700 and 2750 Multimeter/Switch Systems. The Model 7711 and 7712 RF Switch Modules give manufacturers of telecommunications devices and related products economical, wideband signal routing solutions that complement the already
powerful DC/low frequency switching and measurement capabilities of the 2700 and 2750 mainframes. When used with either mainframe, the Model 7712 is the only solution of this type
that offers RF switching to 3.5GHz for applications like 3G telecom, wireless LAN, and Bluetooth module testing. The companion Model 7711 provides low cost, general purpose RF
switching to 2GHz. The tight integration of these modules in a two-slot (2700) or five-slot (2750) multimeter/switch mainframe allows manufacturers to build multichannel DC/RF test systems for
automated test applications with fewer pieces of equipment. The result is faster test times, reduced rack space, easier programming, lower cost of ownership, and improved ROI on test instruments. Both modules offer a 50 OHM, dual 1x4 multiplexer configuration with rear panel SMA connectors. The rear panel connectors eliminate the need for clumsy adapter cables to internal connections, and provide superior RF performance compared to alternative systems. Multiple 1x4 multiplexers can be cascaded to build scalable matrix and multiplexer systems for a large number of devices under test (DUTs) and RF source/measuring instruments. These modules can be mixed with any of the nine other modules available for the Series 27xx mainframes (which contain up to five card slots). Users can create highly versatile DC/RF test systems with a combination of channel count, cost per channel, and RF system performance superior to any other single-box measurement/switch system.

Applications and Markets. The Model 77xx RF Switch Modules are designed for low-loss RF and digital signal routing in test systems used by manufacturers in telecom, aerospace/defense,
electronic component, and related industries. They are intended for switched connections between DUTs and instruments such as oscilloscopes, function generators, power meters, network analyzers, bit error rate testers, and spectrum analyzers. Application examples include:
* Production test of communications/networking products such as Bluetooth, wireless LAN, and 3G cell phones.
* Characterization and burn-in of high frequency components like oscillators, amplifiers, and filters.
* AC ripple and noise test for switching power supplies and DC-DC converters.

Application Background. RF switching allows integrating high frequency measurements with DC electrical testing, and supports a higher level of automation that minimizes operator involvement. The ability to switch RF signals between multiple input and output channels is increasingly vital as manufacturers strive to make DC/RF production testing more efficient.

Product Details. The Model 7711 and 7712 RF Switch Modules are designed for installation in the expansion slots of a Series 27xx mainframe for routing 50 OHM signals to/from external RF
instrumentals and DUTs. The contact configurations of the high frequency electromechanical relays of these modules are dual 1x4 multiplexers (single-pole/four-throw), with Channels 1 and
5 normally closed. Relay actuation time is less than l0ms. The module allows flexible signal routing, with either local control through the 27xx mainframe's front panel or remote PC control
over the GPIB or RS-232 interface. The maximum signal level is 30Vrms or 60VDC (30VDC for 7712), 0.5A, up to 10W per channel and 20W per module. The following table shows typical AC switch performance for Zload = Zsource = 50 ohms:

Model 7712 2.4GHz
Insertion Loss 0.7dB
VSWR 1.15
Ch-Ch Crosstalk -55dB
Model 7711 1GHz
Insertion Loss 0.5dB
VSWR 1.05
Ch-Ch Crosstalk -65dB

The Model 2700 and 2750 mainframes have 14 built-in digital multimeter functions, including DCV, DCI, ACV, ACI, resistance, frequency, and temperature. The 6-1/2-digit resolution of the
DMM supplies highly reliable, repeatable measurements that reduce false failure indications and improve product yields. The nine other 77xx plug-in modules provide DC/low frequency switching of up to 200 differential multiplexer channels or 240 matrix crosspoints. These modules also add analog output, digital I/O, counter/totalizer, and control capabilities to the 27xx platform.

Price and Availability. Keithley's Model 7111 RF Switch Module has a list price of $495, and the Model 7112 is priced at $1995. Both are available from stock.

About Keithley Instruments. Keithley Instruments, Inc. provides electrical, RF (radio frequency), and optical measurement solutions to the telecommunications, semiconductor, optoelectronics, and other electronics manufacturing industries. Engineers and scientists around the world use Keithley's advanced hardware and software for process monitoring, production
test, and basic research.