Flying probe and in-circuit testers (ICT) are used to test printed circuit board assemblies (PCBAs) to ensure quality and functionality.

However, they have some differences in operation, flexibility, and cost-effectiveness.

A flying probe tester is a fixtureless testing tool that utilizes multiple movable test probes to contact specific points on the PCB. It measures the electrical properties of components and checks for shorts, opens, or incorrect component values.

In-circuit testers use a custom test fixture, known as a "bed of nails," to make contact with test points on the PCB. In-circuit testers are generally more suitable for medium to large-scale production.

Flying Probe Testers - key points

• No need for custom test fixtures: Flying probe testers do not require test fixtures, making them suitable for low to medium-volume production runs and ideal for prototyping and rapid design changes.
• Flexibility: They can easily adapt to different PCB designs and test complex, dense boards.
• Shorter setup time: generating test programs is usually quick, and Test programs can be updated to accommodate design changes, enabling faster testing turnaround and reducing production delays.
• Lower operating cost: elimination of fixture costs reduces NRE costs, making flying probe testing more cost-effective for prototypes and small to medium production runs.
  
  

In-Circuit Testers - key points

• Custom test fixtures: ICT uses custom test fixtures, often called "bed of nails," to contact test points on a circuit assembly.
• Medium to high-volume production: Electronic manufacturers typically use ICT for medium to high-volume production.
• High test speed: In-circuit testers can perform tests faster than flying probe testers, as they can access multiple test points simultaneously, making them suitable for high-volume production.
• Higher initial cost/NRE: The custom test fixtures required for ICT can be expensive, especially for low-volume production or prototypes.
• Longer test development time: Designing and manufacturing custom test fixtures can lead to more prolonged setup times.
• Less flexibility: Any changes in the PCB design may require updates to the test fixture, increasing test preparation time and cost. This makes ICT less adaptable to frequent design changes than flying probe testers.