Scaling Production Test Without Scaling Complexity

Production test teams often need to balance two competing priorities: improving throughput while keeping test development practical and maintainable. As product volumes increase, parallel testing becomes an attractive option because it allows multiple devices under test (DUTs) to run at the same time. In practice, however, multi-DUT execution can introduce duplicated test logic, instrument contention, synchronization issues, and additional maintenance effort.

The Multi-DUT Threading feature in PTEM helps address these challenges by simplifying how multi-DUT test plans are created, executed, and maintained.

One test plan for multiple DUTs

Fig. 1: Duplicated test sequences used to test DUTs in parallel.

Traditionally, scaling from single-DUT to multi-DUT testing requires either duplicating test flows for each DUT or writing custom control logic to manage execution across devices.

Both approaches add complexity and increase the risk of inconsistencies across DUTs. Even small updates, such as adding a measurement or adjusting limits, must be replicated carefully, which slows iteration and increases the chance of errors.

Fig. 2: No duplicated test steps are needed when testing all DUTs using Multi-DUT Threading.

PTEM takes a different approach. You define one set of test steps, and the system dynamically creates virtual instances for each DUT. This lets test developers work with one logical test definition instead of maintaining multiple physical execution paths. There is no need to duplicate test steps for each DUT. You can run all DUTs at the same time by clicking the Run All button or target a specific DUT by selecting it from the Target DUT box and clicking Run DUT.

Example comparison:

Table 1: Effort and risk comparison using Multi-DUT Threading.

In practice, this reduces development time and makes test plans easier to review, validate, and maintain as production requirements change.

Built-in instrument coordination without manual locking

One of the most common challenges in parallel testing is managing access to shared instruments.

Consider a setup where three DUTs share a single digital multimeter (DMM). In a conventional system, the developer typically needs to implement locking mechanisms, manually serialize access, and debug race conditions or resource conflicts.

This increases code complexity and can introduce subtle bugs that only appear under load or during long production runs.

Fig. 3: Same instrument intelligently shared across multiple DUTs with PTEM Multi-DUT Threading.

PTEM removes much of this burden by automatically handling instrument access through an internal queuing mechanism. When multiple DUTs request the same instrument, PTEM queues the requests, executes them sequentially, and helps ensure safe, conflict-free operation.

From the test developer’s perspective, this behavior is transparent. Test steps can be written as if resources are available when needed, while PTEM manages shared access behind the scenes.

Practical impact: This eliminates a common source of test bugs, improves system reliability and measurement integrity, and reduces development effort in multi-DUT environments.

Higher throughput without compromising test safety

At first glance, sequential instrument execution may look like a bottleneck. In real-world test plans, however, not every step uses the same resource. PTEM allows independent steps, such as arithmetic and logic operations, delays, and string processing, to run in parallel while serializing only the shared instrument usage. This improves overall throughput even when some resources must be shared.

Manual implementations often fall into one of two extremes: over-serialization, where entire test flows are unnecessarily forced to run one at a time, or unsafe parallel access, which can result in invalid measurements or hardware-related issues.

PTEM helps optimize this balance automatically, allowing teams to increase throughput without adding custom coordination logic. Test plans remain lean, readable, and easier to maintain.

Flexible parameter control for each DUT

Another common production requirement is handling device-to-device variation. Not every DUT behaves identically; some may require different limits, offsets, channels, or calibration conditions.

In many systems, supporting these differences requires conditional logic embedded in the test flow, external configuration files, lookup tables, or separate test variants that must be maintained independently.

Fig. 4: A single test step can run with different DUT-specific parameters for each DUT.

PTEM simplifies this through DUT-specific parameters directly within the test plan editor. You can select the target DUT, modify any parameter in the test step, and PTEM converts it into a DUT-specific parameter. The parameter is also tagged with a DUT label, making it easy to distinguish from other common parameters. In a single test step, you can have parameter values that are unique to the DUT.

Example in the Source Voltage step:

• DUT 1 connects and uses DAC Channel 05
• DUT 2 connects and uses DAC Channel 04

No additional scripting or branching is required. The parameters are clearly labeled, which improves visibility and traceability during debugging, validation, or audits.

Why this matters to engineering and operations teams

For engineers, PTEM reduces coding and debugging effort, keeps test plans cleaner and easier to maintain, and helps avoid synchronization and concurrency issues that commonly appear in multi-DUT systems. For managers, the value is equally clear: faster test development cycles, more consistent deployment, improved test reliability, and better scalability as product volumes increase.

Bringing it all together

With Multi-DUT Threading, multi-DUT testing does not have to create exponential complexity. PTEM combines single-definition test plans, automatic instrument queuing, built-in multi-DUT threading, and flexible parameter control to help teams scale production test systems more efficiently.

By reducing unnecessary engineering overhead, PTEM allows teams to focus on test coverage, measurement quality, and production readiness instead of managing custom threading and resource coordination.

The result is a more robust and scalable production test environment that balances throughput, safety, and maintainability while keeping development effort under control.

For a visual walkthrough of PTEM capabilities, visit the Keysight Hands-On channel on YouTube and look for the PathWave Test Executive for Manufacturing playlist.