User-programmable FPGAs in your measurement system hardware provide benefits ranging from low-latency DUT control to CPU load reduction. The following sections describe various usage scenarios in more detail.
Improve Test System Integration with Onboard Decision Making
In many test systems, the device or chip under control must be controlled via digital signals. Traditional automated test systems can sequence through DUT modes and take the needed measurements in each stage. In some cases, automated test equipment (ATE) systems incorporate intelligence to progress between DUT settings according to the measurement values received.
In either scenario, software-designed instruments that incorporate a user-programmable FPGA result in cost and time savings. Consolidating measurement processing and digital control into a single instrument reduces the need for additional digital I/O in the system and avoids configuring triggering between instruments. In cases where the DUT must be controlled in response to measurement data received, software-designed instrumentation closes the loop in hardware and reduces the need for decision making in software at a significantly higher latency.
Decrease Test Time and Increase Confidence with In-Hardware Measurements
Today’s software-based test systems can perform a limited number of measurements in parallel, but software-designed instrumentation is limited only by the available FPGA logic. You can process dozens of measurements or data channels with true hardware parallelism, removing the need to choose between measurements of interest. With software-designed instruments, functionality such as real-time spectral masking is achieved with dramatically higher performance and at a fraction of the cost compared to traditional boxed instruments.
The low latency associated with performing measurements in software-designed instruments means that tens or hundreds of live measurements can be taken and averaged together in the same amount of time a traditional test system requires to take a single measurement. This results in improved test-result quality and increased confidence in your measurements.
Focus Only on Interesting Data with Custom-Defined Triggers
Traditional instrument options for low-latency trigger behavior are fixed according to the hardware being used, but with software-designed instrumentation you can incorporate custom triggering functionality into your device to quickly zero in on situations of interest. Flexible hardware-based triggering means that you can implement custom spectral masks or other complex conditions as criteria for either capturing important measurement data or activating additional instrumentation equipment.
Reduce CPU Processing Loads with Real-Time Onboard Signal Processing
Processing large amounts of data can tax even the most capable commercial CPUs, resulting in systems with multiple processors or extended test times. With software-designed instrumentation you can preprocess data in the hardware, potentially reducing the CPU load significantly. Computations such as fast Fourier transforms (FFTs), filtering, digital downconversion, and channelization are implemented in hardware, reducing the amount of data passed to and processed by the CPU.
Gain Confidence in Final Design Performance With Rapid Prototyping
Engineers and scientists traditionally use instrumentation just for test and measurement applications, but the connectivity between I/O and software in modular instruments enables you to prototype electronic systems using instrumentation. As an example, engineers can prototype advanced radar systems using digitizers and RF signal analyzers; the connectivity to a user-programmable FPGA allows quicker advanced algorithm deployment in prototype and faster proof-of-concept validation.
Validate Serial Interfaces with Protocol-Aware Test
Modern data communication protocols have transitioned from parallel interfaces to high-speed serial interfaces such as PCI Express, HDMI, DisplayPort video standards, IEEE 1394b, and USB 3.0. For design and test engineers, validating these interfaces presents new challenges and requires new test hardware. Traditionally, engineers employ very expensive oscilloscopes or bit error rate testers to characterize physical interfaces, and protocol-specific analyzers and generators to validate correct protocol stack implementation and efficient data transmission and reception. User-programmable FPGAs offer an intriguing solution to these challenges. Modern, high-performance FPGAs generally include several multigigabit transceivers that support a variety of high-speed serial interfaces. Combined with the appropriate protocol-specific IP, graphical LabVIEW FPGA programming, and the advantages of the PXI ecosystem, a new type of instrument emerges—a high-speed serial, software-designed instrument.