SMD inductors

Custom SMD inductors – Design and manufacture of dedicated SMD chokes for surface mounting in modern electronics

The miniaturization of electronics, rising operating frequencies, and increasing electromagnetic compatibility requirements are driving a dynamic increase in demand for dedicated SMD inductors. Modern SMD surface-mount chokes are a key component of power supply systems, signal filtering, and electromagnetic interference (EMI) control.

What are SMD inductors?

SMD chokes (Surface Mount Devices) are passive inductive components designed for automatic placement on the surface of printed circuit boards (PCBs) using surface mount technology (SMT). Nowadays, SMD chokes can be found in most electronic systems – wherever there’s a PCB and a power supply, there will be SMD chokes: antenna systems, signal filtering systems, transceivers, switching power supplies, automotive electronics, IoT devices, telecommunications, medical equipment, embedded systems, industrial electronics, RF and 5G devices.

Modern SMD chokes are designed to maintain high power density, a low profile, high switching frequency, and minimize losses.

The production of dedicated, custom SMD chokes for surface mount applications typically includes core selection for the target PCB design, winding design, thermal optimization, and electrical parameter measurements. Various SMD choke designs are available, depending on the customer’s specific requirements.

Below are the approximate ranges of electrical and mechanical parameters:

PARAMETER	SMD CHOKES
Wire type	Solderable and non-solderable: CuL 155 – 200, Gr.1 – 2 (typically) Selfbonding: FSP 18, STP 18, PSP 15 and etc.
	CuAg silver-plated wires for HF applications
Other types of wires are available on request.
Wire diameter	Min	0,1 mm
	Max	2,10 mm
	Other wire diameters are available on request.
Winding direction	Left, Right
Number of winding layers	Min	1
	Max	TBD
Coil shape	Depends on the shape of the ferrite core. Cylindrical, spool, bar, and others.
	Possibility of placing a UV glue point for automatic assembly (Pick & Place machines).
	Unusual, non-typical shapes or requirements – Possibility of individual arrangement upon request.
Types of cores used	Ferrite Cores, Powder Cores, Metal Composite
Typical saturation current ranges (Isat)	0,1 A (100 mA) 1 A 5 A 10 A
Typical DC resistance (DCR)	below 1 mΩ (in VRM and Automotive), 2 – 100 mΩ for medium power
Typical operating frequency	Depends on the application and the choice of materials (especially the hysteresis of the ferrite core) 100 kHz 250 kHz 500 kHz 1 MHz
Leads	Typically – soldered to the core.
	Thermocompression welded
	Metalized with silver wire for reinforcement
	Other versions are available upon request
Location and shape of pins	Typically – wrapping around specific core points
	Depending on the core shape – pinout according to the core and customer requirements
Soldering	Pb-Free
	Pb (on request)