Moving from the Bench-Top to Production
High volume consumer end products and sub-assemblies have traditionally been tested on low cost, custom built, fully integrated bench-top equipment. These systems are typically created in-house and combine test resources from multiple vendors into a single test setup for a particular device. These custom solutions require considerable development effort, are focused on a particular device design, and require the designer to keep the tester capabilities up to date. In high frequency cases, each setup can have unique interfaces and signal conditioning that requires specific setups, calibration requirements, and maintenance needs that all significantly increase the complexity and cost of test.
Modern ATE Alternative
Roos Instruments developed the Cassini platform to address the growing need of a more flexible ATE solution that provides the tools to transition to high volume test with ease. This evolutionary leap forward in production measurement provides a low cost, modular architecture capable of digital, mixed-signal, and RF device test from DC to more than 80GHz to support current ICs as well as emerging multiple-chip module and system on a chip architectures. To simplify the development process and streamline the movement of bench measurement to production test, Cassini combines measurement design, test automation, and production logistics into a single workflow.
The measurement hardware was designed to provide expandable capabilities and work seamlessly with the software to provide fast, accurate, and repeatable measurements. Cassini provides test capability via a series of Roos Instrument and third party Test Instrument Modules (TIMs). Each TIM is a stand-alone solution with self-contained signal delivery and thermal management. Some TIMs are targeted against general purpose test coverage and provide a long term backbone for a broad range of device coverage. Other TIMs are developed for specific test requirements and can be configured as needed for a particular market or industry. This combination allows continuous development of new TIM technology for emerging markets with short lead times and proportional cost of development. In this environment ROI can sometimes be justified on a project or market basis. TIM focused solutions provide flexibility with simple module interchange or upgrade as well. Manufacturing managers no longer need to predict the future and can provide their product groups with state-of-the art test coverage that adapts to the demands of the market without excess cost.
Cassini's base platform includes the mechanical and electrical interfacing needed to support robotic material handling integration with wafer Probers and package part Handlers via standard GPIB, parallel or serial connections. Such capability must be individually designed into each integrated bench top test cell if it is even done at all.
Integrated Development Environment
ATE generally has a fully integrated software development environment, Cassini is no exception. The advantage is that all instruments in the tester have a very similar look and feel in terms of their programming environment. In fact, the user generally approaches each test procedure from an overall system view as opposed to an assemblage of individual instruments. The net benefit is increased productivity during programming and debug. So once again, a shorter path to production test.
Integrated Calibration Scheme
High performance RF measurements require a very carefully designed and executed calibration process. Bench-top solutions involve unique calibration design, integration and compensation on a per instrument basis for each station. Significant planned and unplanned downtime of the test cell can result. Highly trained service personnel with specific skills may be needed at each site as well. If not done correctly, the cost is measured in yield loss or shipment of bad product. Cassini is a continuum of the 20 years worth of calibration methodology developed for the RI7100A, RI's popular legacy platform. Calibration consists of a system level application extended to fixtures, DUT boards, test sockets and probes with fully integrated embedding capability, creating a tiered calibration scheme. Calibration data for each layer is collected by a routine test plan at each level of the hardware. Once this data exists, the Cassini development software embeds all the needed calibration information for respective hardware in each setup into the job plan as part of a compile procedure executed at run time.
There are multiple benefits to this:
- Any fixture can run on any tester. In other words each tester is NOT unique at run time.
- Operators and service personnel do not require special skills on a test cell by test cell basis.
- Test development engineers do not need to include offset information in each test plan for each given test cell. So one single test plan will work with any combination of tester, fixture, DUT board.
One Tester - Multiple Devices
One of the most important long term benefits of a Cassini in a production test environment is that it is a system which can support multiple configurations and fixtures, for testing multiple product types. Both horizontal and vertical expansion is supported. For instance, a mmWave tester used for low volume but high performance backhaul devices can also be used for very high volume 802.11 products. So the investment can support growth into multiple markets at the same time.
True Low Cost Production Test
Cassini Test Systems scale to provide optimal cost performance for single site or multi-site test requirements. This provides a lower single site cost-of-test (COT) at single site configurations than quad or octal site solutions on many general purpose ATE testers. The key advantages here are:
- Faster time to market with low risk single site test
- Market leading COT when upgraded to dual or quad site test
For more information about our products and services, contact RI at 408-748-8589, [email protected], or visit www.roos.com