Fixed Inductors

Part Number	Description / PDF	Quantity
LQW2BHN27NJ03L TOKO / Murata	FIXED IND 27NH 540MA 170 MOHM	966
DD1274AS-H-3R3N=P3 TOKO / Murata	FIXED IND 3.3UH 7.4A 11.4 MOHM	280
LQP03TG3N9B02D TOKO / Murata	FIXED IND 3.9NH 350MA 350 MOHM	0
LQG18HH3N9S00D TOKO / Murata	FIXED IND 3.9NH 450MA 150 MOHM	3051
LQG15WH4N3S02D TOKO / Murata	FIXED IND 4.3NH 800MA 100 MOHM	9955
LQW2BHNR18J03L TOKO / Murata	FIXED IND 180NH 250MA 710 MOHM	3069
LQH31CN101K03L TOKO / Murata	FIXED IND 100UH 80MA 15.6 OHM	148394
LQW2BASR24G00L TOKO / Murata	FIXED IND 240NH 350MA 1 OHM SMD	0
LQP03HQ5N6H02D TOKO / Murata	FIXED IND 5.6NH 400MA 250 MOHM	18652
LQP02HQ1N4C02L TOKO / Murata	FIXED IND 1.4NH 700MA 80 MOHM	0
LQP15MN10NG02D TOKO / Murata	FIXED IND 10NH 100MA 1.3 OHM SMD	16240
LQH44PN220MP0L TOKO / Murata	FIXED IND 22UH 790MA 444 MOHM	102
LQP02HQ15NJ02L TOKO / Murata	FIXED IND 15NH 170MA 1.53 OHM	0
LQP02HQ1N6C02E TOKO / Murata	FIXED IND 1.6NH 700MA 80 MOHM	0
LQP02TN2N3B02D TOKO / Murata	FIXED IND 2.3NH 200MA 750 MOHM	0
LQW03AW12NJ00D TOKO / Murata	FIXED IND 12.5NH 280MA 540 MOHM	368
LQP03TQ1N1W02D TOKO / Murata	FIXED IND 1.1NH 800MA 80 MOHM	11927
LQW15AN8N3G8ZD TOKO / Murata	FIXED IND 8.3NH 1.5A 69 MOHM	9320
LQB15NNR47M10D TOKO / Murata	FIXED IND 470NH 300MA 800 MOHM	0
LQG15WH2N9S02D TOKO / Murata	FIXED IND 2.9NH 900MA 80 MOHM	9910

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