Fixed Inductors

Part Number	Description / PDF	Quantity
506WLSN3R30KT350T American Technical Ceramics	FIXED IND 3.3UH 350MA 1.2 OHM	112
506WLSN10R7KT150T American Technical Ceramics	FIXED IND 10.7UH 150MA 7.1 OHM	115
506WLSM2R00KT277T American Technical Ceramics	FIXED IND 2UH 277MA 1.6 OHM SMD	9282800
506WLSN2R00KT494T American Technical Ceramics	FIXED IND 2UH 494MA 650 MOHM SMD	21
506WLSN6R00KT236T American Technical Ceramics	FIXED IND 6UH 236MA 2.8 OHM SMD	400
506WLSN1R47KT694T American Technical Ceramics	FIXED IND 1.47UH 694MA 330 MOHM	0
506WLSM0R47KT815T American Technical Ceramics	FIXED IND 470NH 815MA 190 MOHM	719
506WLSM0R70KT619T American Technical Ceramics	FIXED IND 700NH 619MA 320 MOHM	4013600
506WLSM1R10KT438T American Technical Ceramics	FIXED IND 1.1UH 438MA 640 MOHM	208
506WLSM3R80KT182T American Technical Ceramics	FIXED IND 3.8UH 182MA 3.7 OHM	108
506WLC2R0KG250B American Technical Ceramics	FIXED IND 2UH 250MA 1.45 OHM TH	0

Fixed Inductors

1. Overview

Fixed inductors are passive electronic components designed to store energy in magnetic fields when electrical current flows through them. Unlike variable inductors, their inductance values remain constant during operation. These components play critical roles in filtering, signal processing, energy storage, and electromagnetic interference (EMI) suppression across modern electronics, including power supplies, communication systems, and automotive electronics.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Wirewound Inductors	High precision, high current handling, low resistance	Power supplies, DC-DC converters
Chip Inductors	Compact SMD package, stable performance at high frequencies	Mobile devices, RF circuits
Ferrite Bead Inductors	Effective high-frequency noise suppression	EMI filtering in digital circuits
Thin-Film Inductors	Ultra-compact, high Q-factor, tight tolerance	5G communication modules, IoT devices

3. Structure and Composition

Typical fixed inductors consist of:

Magnetic Core: Made from ferrite, powdered iron, or composite materials to concentrate magnetic flux
Coil Structure: Copper wire wound around the core (enamelled or silver-plated)
Encapsulation: Molded resin or ceramic coating for mechanical protection and insulation
Terminations: Solder-coated ends for PCB mounting (for SMD types) or leaded connections

4. Key Technical Specifications

Parameter	Description	Importance
Inductance (L)	Measured in henrys (H), determines energy storage capacity	Defines filtering/energy storage performance
Rated Current (I_rated)	Maximum DC current before saturation	Prevents core saturation and failure
DC Resistance (DCR)	Resistance of coil windings	Affects efficiency and thermal performance
Self-Resonant Frequency (SRF)	Frequency where inductor behaves as capacitor	Limits effective operating frequency range
Q Factor	Quality factor indicating efficiency	Higher Q = lower energy losses

5. Application Fields

Consumer Electronics: Smartphones, laptops, LED drivers
Industrial Equipment: Motor drives, power inverters
Automotive Systems: ECU modules, EV battery management
Telecom Infrastructure: Base station filters, optical transceivers

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Murata	LQH3NPN100M	10 H, 1.2A, 1.8 1.4mm chip inductor
TDK	MLZ2012A100T	100MHz SRF, 1.0 1.25mm for RF circuits
Vishay	IHLP2525CZER1R0M	1 H, 12A, composite construction
Coilcraft	0402DC-103J	10 H, 5% tolerance, ultra-low profile

7. Selection Guidelines

Key considerations during selection:

Calculate required inductance based on switching frequency and ripple current
Verify rated current exceeds maximum operating current by 20-30%
Select SRF higher than circuit operating frequency
Consider package size vs. thermal dissipation requirements
For EMI suppression: Choose ferrite beads with impedance curves matching target frequencies

8. Industry Trends

Current development trends include:

Miniaturization: Sub-0.5mm size inductors for wearable devices
High-Frequency Operation: Components supporting >10GHz 5G applications
Integrated Solutions: Combined inductor-filter modules
Material Innovation: Nanocrystalline cores for higher saturation flux
Automotive Focus: AEC-Q qualified parts for EV/HEV systems