Siemens Digital Industries Software recently announced its Tessent AnalogTest software solution, the so-called first automated design for test (DFT) solution for analog circuitry in integrated circuits.

The AnalogTest comes as a module for Siemens’ Tessent Silicon Lifecycle Solution. Tessent includes debug, security features, and operational data analytics for designing, testing, and maintaining ICs. The AnalogTest addition brings analog and mixed signal IC capability to Tessent. The end result is a 100x improvement in analog and mixed-signal circuit test time over existing manual test methods.

Automated Design for Test Comes to Analog ICs

While virtually all digital ICs are developed in concert with automated test, the same cannot be said for analog and mixed-signal ICs. Automated digital tests can involve complex logic and algorithms, but like the IC under test, they are two-dimensional. Results and verification come as digital numbers and patterns.

Analog testing, on the other hand, requires verification of complex signals, including amplitude, frequency, slope, shape, and more. Verifying these signal attributes requires extremely expensive mixed-signal test equipment, manual pattern generation, and designing and building custom verification circuitry.

The Tessent AnalogTest software automates much of this process by analyzing individual circuit blocks and automatically generating the appropriate test circuitry along with corresponding digital test patterns. Such a test can then be run in less than a millisecond with common test equipment.

A Standards-Compliant Interface

In addition to automating test pattern design, the new software solution enables verification with digital automated test equipment (ATE) instead of with more expensive and time-intensive high-end, mixed-signal equipment. With this capability, validation engineers can verify high (>90%) IEEE P2427-based defect coverage in a matter of hours for individual circuit blocks— something that could take months with manual methods.

AnalogTest delivers simulation test benches based on developers' specification definitions. The test circuitry relies on Instrument Connectivity Language (ICL) and Procedural Description Language (PDL) constructs to define and access the various internal, self, and external text algorithms. This promotes compatibility with the Tessent software and IEEE 1687 (JTAG)-compliant test equipment.

The resulting test capability extends to defect coverage for algorithmic trimming and top-up parametric tests. AnalogTest testbenches are compliant with ISO 26262 functional safety metrics to allow use in automotive-grade components.

The Software in Action

AnalogTest has already been put to use in the real world. When Onsemi engineers applied the software to a recent IC design project, the tool allowed them to reach more than 95% of analog defect coverage and reduce the test time by 100x.

AnalogTest sits as a module inside Siemens’ Tessent lifecycle management software suite. The Tessent suite follows IC design from the beginning with DFT, functional test, stress testing, yield tracking, and other lifecycle management tools. The new AnalogTest tool is currently in use by Onsemi and other selected partners. It will be available for general release in December 2025.

By: DocMemory
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