Wireless Fixtures for MTS300 SIGMA
Faster Fixture Manufacturing & Better Signal Quality
In the early 1980' s designing fixtures was a lengthy process that took 3-6 weeks following the signals from one component pin to the other and placing a test point at the best possible place. Digitaltest's C-LINK and similar products that came later to the market reduced this process to time-frames of less than a few hours, but fixture manufacturing continues to be a process that takes between 3 to 6 weeks. At Digitaltest, we are always looking for ways and tools to reduce the time to test.

Wired Fixture
Classical fixtures that are using wires between the fixture interface and the fixture itself have the following disadvantages:
• Long wires limit the quality of the signals
• High residual capacitance which can be different from one fixture to the other
• Sensitive signals need twisted pairs
• Long production time
• Since they are wired manually they are prone to errors that require long debugging time
• N fixtures need N times the costs and the time.

Traditional Wireless fixture

The idea of a wireless fixture is not new. Wireless fixtures have the following disadvantages:
• Through pin multiplexing certain pins must be wired to certain locations. The net list of the PCB, that will include the fixture wiring, is given through the pin multiplexing algorithm of the tester and is not necessarily the shortest path.
• In most cases, the layout of the board is rather complex and designing the PCB could be very time consuming and expensive.
• In many cases, a multi-layer board is required, which increases the costs and possibly the production time as well.
• Modifications are very tedious.
• The nails of the fixtures and system are touching the pads with every actuation making the pads more prone to damage and the lifetime of the fixture limited.

Wireless fixture for the MTS300 SIGMA tester
The major advantage of the MTS tester family is the non-multiplexed pin architecture. The fact that all of the pins are similar makes the task of creating a wireless fixture much easier. Designing a wireless fixture on an MTS tester will involve simply looking for the next tester pin.

An Auto-Router will use the net list generated to create the design data for the PCB. This will only take between 5-20 minutes. Because the fixture interface of the MTS300 SIGMA has large dimensions and the tester pins are equally distributed, the task will be done through a 2 layer board in over 95% of the cases.

The design procedure takes measurements to ensure that fixture modifications are an easy task.

The advantages of the Wireless fixture provided by Digitaltest
• Short time for fixture design (just few hours)
• Two layer PCB is sufficient in most cases, i.e. inexpensive costs for the PCB
• No manual intervention guarantees fault-free fixture Short wire fixture
• Low residual capacitance and impedance that are identical between several fixtures
• Low residual capacitance and impedance that are identical between several fixtures
• The 2nd fixture will cost less than the first one
• Comes with counter for the no. of actuations, Fixture ID for automatic program loading
• Price compatible with the wired fixtures
• Shorter time for production (one to two weeks)

Digitaltest can provide the Fixture Kit and design the fixture for its customer.