Custom Micro Air-Core Coils for Medical Sensors and Precision Instruments

A medical equipment manufacturer was developing a compact sensing module for a portable monitoring instrument. The module required a miniature air-core coil with a high number of turns, but the available installation space was restricted by the sensor housing and PCB layout.

The first sample used a standard miniature coil. Although the basic inductance value was close to the target, the customer found variation between samples after assembly. Changes in coil diameter, lead position, and winding tension affected the sensor signal and made it difficult to maintain consistent calibration.

Golden Eagle reviewed the required inductance, tolerance, wire diameter, number of turns, inner diameter, outer diameter, coil height, Q value, resistance, lead length, terminal position, assembly method, and operating environment. The design was adjusted to balance electrical performance, mechanical dimensions, winding accuracy, and production feasibility.

For fine-wire, high-turn coils, tension control is critical. Excessive tension may deform the coil or damage the enamel insulation, while insufficient tension may cause loose winding and dimensional variation. The winding process must also control the number of turns, layer arrangement, coil shape, and lead position.

Golden Eagle developed samples using a controlled precision-winding process. The customer evaluated inductance, resistance, Q value, dimensions, turn count, insulation condition, lead strength, assembly fit, sensor output, calibration repeatability, and batch consistency. Testing the coil after installation was important because the final housing and nearby materials could influence the electrical performance.

The customized micro air-core coil helped the customer improve the repeatability of the sensing module and establish clearer production tolerances. It also allowed the engineering team to identify which dimensions had the greatest impact on the sensor signal before moving to volume production.

Golden Eagle has 15 years of R&D and manufacturing experience in coils, inductors, transformers, and wireless charging components. Suitable projects may receive prototype support within approximately 3–5 days. Any medical application requirements, material restrictions, inspection standards, and validation results must be confirmed according to the customer's technical documentation.

When sourcing a miniature air-core coil, buyers should provide the target inductance, tolerance, wire diameter, number of turns, Q value, resistance limit, coil dimensions, lead structure, installation drawing, operating temperature, assembly method, sample quantity, and annual demand.

Golden Eagle supports custom fine-wire coils, high-turn coils, RF coils, sensor coils, air-core coils, and other precision magnetic components for medical instruments, industrial sensors, wearable devices, and compact electronic modules.