Analog Devices AD7142 Sensor Board In-Line Production Test Procedure
Guidelines for in-line testing of the AD7142 capacitance-to-digital converter sensor board to ensure correct host connectivity and sensor operation using excitation source tests.
Overview
This application note (AN-858) defines the in-line production testing procedure for sensor boards featuring the Analog Devices AD7142 capacitance-to-digital converter. The procedure facilitates verification of the connection between the sensor board and the system host controller, while also confirming that the sensor elements operate correctly. Testing is performed by monitoring the ADC_RESULTS_Sx registers while enabling and disabling the device's internal excitation source (SRC). The document provides a methodology for sensor characterization to establish mean baseline values and a step-by-step in-line test flow to identify manufacturing defects or out-of-range sensor performance.
Use Cases
- Manufacturing quality control for AD7142-based capacitive sensor boards
- In-line production testing for consumer electronics touch interfaces
- Verifying host-to-sensor board connectivity during assembly
- Troubleshooting faulty capacitive sensor elements in production