Signal and power components to handle harsh environments. Industrial control, coils for sensor and monitoring applications, switched mode components for battery chargers, EMC components etc.
Case Study: High-Q Inductor
A UK company was looking for a low cost high performance solution for a precision inductor capable of achieving a Q of 200 over 270 – 550 kHz, with an inductance tolerance around 1%. After a search the customer was unable to find standard inductors achieved this high Q, which was required for selectivity in a tuned circuit.
Because of the intended application, a closed magnetic circuit was desirable to prevent magnetic coupling, frequency pulling, and losses, but closed magnetic circuit topologies are inherently more expensive. Additionally, the design would require litz wire and special low loss signal ferrite grades to achieve the high Q, though these also added to the cost considerably, and the close tolerance would also have impact on yield and machining costs.
The solution was non-trivial because there are so many tradeoffs: thinner strands in the litz wire improve Q but increase cost; fewer winding layers reduce proximity effect losses, but increase hysteresis losses etc. The proposed solution has been incorporated into thousands of customer’s units.