Fixed Inductors

Part Number	Description / PDF	Quantity
LQW15AN8N3J80D TOKO / Murata	FIXED IND 8.3NH 1.5A 69 MOHM SMD	11154
LQW15AN19NG8ZD TOKO / Murata	FIXED IND 19NH 920MA 156 MOHM	0
#B953AS-330M=P3 TOKO / Murata	FIXED IND 33UH 2.4A 64 MOHM SMD	35
FCUL0530-R47M=P3 TOKO / Murata	FIXED IND 470NH 16A 2.85 MOHM	0
LQH3NPN101MMEL TOKO / Murata	FIXED IND 100UH 270MA 1.908 OHM	2405
LQH43PH101M26L TOKO / Murata	FIXED IND 100UH 320MA 1.8456 OHM	258
LQP02HQ0N4W02E TOKO / Murata	FIXED IND 0.4NH 1A 30 MOHM SMD	0
LQH31HNR21J03L TOKO / Murata	FIXED IND 215NH 520MA 110 MOHM	1278
LQP03TQ2N4B02D TOKO / Murata	FIXED IND 2.4NH 550MA 150 MOHM	12215
LQH32CH100K53L TOKO / Murata	FIXED IND 10UH 450MA 300 MOHM	0
LQM18PHR47MFRL TOKO / Murata	FIXED IND 470NH 1.1A 188 MOHM	4781
LQG15HS4N7B02D TOKO / Murata	FIXED INDUCTOR 4.7NH 0402	30000
LQW2BAN51NG00L TOKO / Murata	FIXED IND 51NH 1.8A 110 MOHM	2080
LQH31MN330K03L TOKO / Murata	FIXED IND 33UH 80MA 4.94 OHM SMD	277
LQW2UASR39G00L TOKO / Murata	FIXED IND 390NH 470MA 1.12 OHM	0
LQH43MN180K03L TOKO / Murata	FIXED IND 18UH 340MA 820 MOHM	0
LQP02TN1N0B02D TOKO / Murata	FIXED IND 1NH 220MA 600 MOHM SMD	0
LQW15AN13NJ8ZD TOKO / Murata	FIXED IND 13NH 1.24A 93 MOHM	0
LQW18CAR33J00D TOKO / Murata	FIXED IND 330NH 780MA 200 MOHM	7368
LQM21DN4R7N00D TOKO / Murata	FIXED IND 4.7UH 30MA 300 MOHM	2381

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