In-Circuit Test Fixtures

The top Automated Test Equipment manufacturers count on Circuit Check. We fabricate and customize in-circuit fixtures for testers made by:

Agilent Aeroflex Digitaltest GenRad Teradyne and others

Customers know they can rely on us for the latest technology as we push the envelope of emerging technologies to meet tomorrow's challenges. More densely populated circuit boards result in test points shrinking down to 0.016" targets and smaller on both surfaces of the board. Guided probe technology is especially important to repeatedly and reliably contact these smaller sized targets as well as Agilent Bead Probe Technology.^® Circuit Check developed the Quick Plate™ to precisely locate the probe tips on these smaller targets to retain testability and further in-circuit's capabilities. The Quick Plate technology can be used successfully on probing those critical top side targets as well as the standard bottom side test pads.

If high speed signal measurements or reduced ground bounce is required for boundary scan testing, Wireless ICT Fixtures are the answer. The design of the Circuit Check T-Board™ never blocks the tester's resources and easily allows the addition of custom circuitry and components to enhance the test. A printed circuit board eliminates the wire bulk and improves tester's performance by reducing the amount of capacitance/inductance the tester's drivers will encounter during high speed digital testing.

Board topography and technology often dictates test methodology and coverage, we match one of three different methods for contacting top side targets to your test specifications. The Signature Series Pneumatic PD was pioneered in the early '80s and refined through the years, allowing it to remain the industry standard for precision, accuracy and repeatability.

Today's 5^th generation Pneumatic PD easily drives as many as 8000 test probes with centerline spacing down to 25mil contacting test pads as small as 0.012". If reliability is in question, it is not uncommon to find PDs with 800K to over a million cycles operating like clockwork still testing products around the world.

A patented vacuum alternative was introduced in the Performance Grade product line several years ago which incorporates several of the favorable attributes of the PD. This exclusive vacuum box design using Auto Align technology to accurately register the top side probes with the bottom side can be used for repeatedly contacting top side test pads down to 0.018", while bottom side test pads of 0.016" are obtainable. This Auto Align design is protected by US Patent 8,004,300.

For less complex and lower density boards a Clam Shell topside probing unit is available in our Value Line. This lower cost alternative easily contacts top side test pads 0.024" in diameter and is extremely reliable for less complex circuit boards.

Hold Down Gates

Hold Down Gates are available for low to medium node count circuit cards when access to the circuit card is required during the test sequence. A Heavy-duty gate with a full frontal latch for higher node fixtures is available for the Performance Grade while a lighter weight cam latch is available for smaller node count circuit cards in the Value Line.

Expanding In-Circuit Test Capabilities

When spring-loaded probes aren't practical or access is limited, use Thru-Connector tests to contact connectors on any surface or edge of a circuit board. These tests can be implemented by a number of methods: spring probes, mating connectors, sacrificial SMT connectors, and stabber cards.

Extend coverage by testing LEDs during in-circuit test. Color, intensity and hue can be checked at ICT eliminating costlier repairs during systems test. The LED test is implemented with industry standard sensors from FINN^®, Optomistic Products and FEASA LED Analyser. Whether placement of the sensor to the LED is direct or remote we can transfer the light through light funnels and light pipes to satisfy test requirements.

Thermal management of electronic components during the testing cycle is very critical for prevention of premature failure. The use of heat dissipation devices becomes essential when combined with vacuum boxes.

Our engineering department matches the thermal energy radiated by the component to the correctly sized heat sink/fan combination to effectively provide the correct cooling solution.

• "Dual Check™" Vacuum Bi-Level fixtures
  Circuit Check introduces a Bi-Level technology that is unique to the industry. This design eliminates the need for any external air or power supply connections. Your test program controls the "Bi-Level" test states using the tester's vacuum ports. There are no mechanical linkages that will malfunction, no levitation of plates, just plain vacuum.
  
  Long stroke probes contact the bottom of your board during the functional or isolation test. Standard stroke probes can contact both top and bottom during the in-circuit portion of the test. Our design allows up to 400 of the long stroke probes, while your tester is the limiting factor for the standard stroke probes.

• "Quick Check™" Interface
  Circuit Check has developed a consistent and cost effective process for marking the interface to quickly and accurately locate populated P-Pins. Previuosly, populated interface locations were difficult to quickly identify as seen below.
  
  Circuit Check's patented "Quick Check™" easily differentiates the populated locations from non-populated locations. Now, during your debug process you can quickly get down to business and not have to worry about whether the interface is correctly loaded. The results are like night and day. The "Quick Check™" interface is accurate, reliable and does not affect the fixture lead times.
  
  
  The "Quick Check™" design is protected by US Patents #7,592,796, #7,749,566 and #7,695,766

Tester Adapters are often utilized when the target ICT tester is not available or has been replaced with a newer technology tester. The tester adapter will often allow existing test fixtures from one tester manufacturer to be utilized on another manufacturers test platform eliminating the need for replacement fixtures. Contact Circuit Check to discuss your tester and fixture combinations for the best choice of a cost effective solution.