Functional Testing

Functional testing is the process of verifying that an electronic device operates as intended, based on design specifications and expected user interactions. Unlike basic electrical checks that confirm power and continuity, functional testing evaluates:

• Logic control and state transitions

• Input/output behavior

• Sensor response

• Communication protocols

• Timing and sequencing

• Display/interface behavior

• Error handling and fail-safe modes

In short, it answers the most important question:
🟢 Does the device do what it’s supposed to do—consistently and reliably?

ProtoLab’s testing services are integrated into our prototyping and assembly workflows. Here’s what to expect:

🧠 Design-Informed Testing

We typically begin testing with:

• Your functional requirements or user flow diagrams

• Your schematic or firmware behavior

• Any specific corner cases or edge conditions to validate

We treat testing as an extension of the design phase, not just a checkbox.

🛠️ Custom Test Setups

We use a variety of tools and techniques, including:

• Oscilloscopes, logic analyzers, multimeters

• Power supplies and electronic loads

• Custom test jigs with pogo pins or headers

• Serial monitors, protocol analyzers (UART, Modbus, CAN)

• Scripted test sequences (optional)

For more complex builds, we can help you develop automated test scripts or build test jigs for ongoing validation.

✅ Test Coverage Examples

Depending on your product type, we may perform functional tests such as:

• Digital Inputs and Outputs – Verify buttons, switches, relays, and GPIO state transitions

• UART / RS485 / I2C / SPI Interfaces – Check communication protocols for correct command/response behavior and signal integrity

• Display and HMI Elements – Confirm screen rendering, refresh rates, button/encoder inputs, and UI logic

• Sensor Inputs – Validate analog or digital sensor readings, including temperature, current, or voltage inputs

• Power Behavior – Assess power-up sequencing, reset behavior, and undervoltage/overvoltage handling

• Output Logic – Test control logic for LEDs, alarms, or actuator outputs

• Timers and Interrupts – Validate real-time response, delay accuracy, and watchdog timers

• Connectivity – Simulate and verify GSM, Wi-Fi, or Ethernet communication including fallback or reconnection scenarios

• Memory and Logging – Confirm EEPROM or flash storage behavior, data retention, and logging cycles

• State Machines and Workflow Logic – Walk through boot states, operation modes, and error handling routines