Zacharia Ouardirhi, Adrien Roy and Arnaud Delias work at Amcad Engineering, as technical sales and business development director, application engineer and project development manager, respectively.

3 November

Providing application engineers with the right software to control instruments, streamline measurements and standardize processes is key to a shorter time to market. This way, they can concentrate on the expertise where they add value: power amplifier design.

Design validation testing of RF/microwave components and circuits is becoming a real challenge for many companies. Eager to get their latest developments to the market, they must achieve performance that highlights the superiority of their products compared to the competition. On the other hand, their customers are continuously requesting additional information on the datasheets. No longer satisfied with simple small-signal measurements and frequency-swept S-parameters, they ask for information related to their specific applications.

Depending on the component and application, the datasheet may include small-signal measurements, frequency sweeps, DC, RF power sweeps, single and two-tone distortion using continuous waves, pulsed and modulated signals. Application engineers try to satisfy their customers’ requests and run different measurement benches to compile all the data. Datasheet generation and formatting represent “60-70 percent of the total work done to take a new IC from prototype test to product launch,” according to the management of a major IC manufacturer.

Amcad setup

Integrating all information

Measurement benches represent the first challenge in the characterization flow. Instruments from different vendors, models and versions are populating the labs of companies in multiple locations. Yet, the measurement results must be aligned from one setup to another no matter who operates the bench or how the measurements are taken. Therefore, instrument-agnostic software must be used to eliminate discrepancies due to instrument manipulation and the necessity to learn all their GUIs.

In discussions with application engineers, the common feedback is the concern about the bench’s versatility with respect to the measurements. Having to dismantle the bench from one set of measurements to another is a major drawback of much in-house-made software. Not to mention the problems linked to the software versions that are different from bench to bench.

The optimum solution integrates a calibration wizard that allows a multi-setup calibration on the same bench. This way, different measurement conditions can be carried out without dismantling the setup and slowing down the testing. Performing S-parameters, power and frequency sweeps, two-tone signal analysis and modulated signal characterization, all these measurements could be carried out in sequence without human intervention, resulting in a considerable time gain and the possibility to perform all the measurements required by the end-customer.

For power amplifier designers, it’s important to perform measurements taking into account the used technology. GaN-based PAs are a good example to illustrate how the characterization needs to be adjusted. From one power sweep to another, the quiescent drain current needs a certain time to settle to the original value. This behavior is due to the trapping effects in GaN transistors. The specifications are wrong if the measurement sequence doesn’t set the appropriate waiting time between different sweeps.

Another challenge faced by the application engineers community is processing and integrating all information in a comprehensive yet easy to generate report or datasheet. This isn’t as simple as it may sound. On the one hand, the right data needs to be chosen to highlight the advantages of the design and make sure it’s complete for the customer to make a decision. On the other hand, there needs to be a streamlined method to generate the datasheet and minimize the post-processing time automatically.

Amcad IQSTAR

Interactive reports

Amcad Engineering has addressed these challenges by developing innovative and advanced measurement software for efficient and accurate circuit testing. The IQSTAR platform is equally suited for S-parameters and CW, pulsed, two-tone and modulated signals with DPD optimization.

IQSTAR also enables the automatic generation of interactive reports to conform with different products and applications. These templates include controls like sliders, filters and extractors. They can import the measurement files, so all the curves are traced, all the tables filled and the merit figures are highlighted automatically.

Edited by Nieke Roos