Fixed Inductors

Part Number	Description / PDF	Quantity
LQW18AN15NJ80D TOKO / Murata	FIXED IND 15NH 1.4A 75 MOHM SMD	0
LQP03TN9N1J02D TOKO / Murata	FIXED IND 9.1NH 250MA 700 MOHM	13417
LQW15AN18NJ00D TOKO / Murata	FIXED IND 18NH 370MA 270 MOHM	210258
LQH32NZ4R7K23L TOKO / Murata	FIXED IND 4.7UH 270MA 1.2 OHM	1880
MBH7045C-680MA=P3 TOKO / Murata	FIXED IND 68UH 1.1A 210 MOHM	0
LQW2UASR10J00L TOKO / Murata	FIXED IND 100NH 650MA 560 MOHM	5135
LQH32NZ390J23L TOKO / Murata	FIXED IND 39UH 110MA 3.9 OHM SMD	1960
LQP15MN3N9B02D TOKO / Murata	FIXED IND 3.9NH 170MA 500 MOHM	0
LQW2BAS68NJ00L TOKO / Murata	FIXED IND 68NH 500MA 380 MOHM	1414
LQG15WH7N3H02D TOKO / Murata	FIXED IND 7.3NH 600MA 170 MOHM	0
LQG15WH33NH02D TOKO / Murata	FIXED IND 33NH 220MA 1.5 OHM SMD	0
LQW15AN4N0B8ZD TOKO / Murata	FIXED IND 4NH 1.95A 30 MOHM SMD	4291
LQG15HH2N7C02D TOKO / Murata	FIXED IND 2.7NH 800MA 120 MOHM	7455
LQP02HQ1N2W02E TOKO / Murata	FIXED IND 1.2NH 800MA 1.1 OHM	0
LQW15AN30NJ80D TOKO / Murata	FIXED IND 30NH 660MA 309 MOHM	3232
DFE201610P-R33M=P2 TOKO / Murata	FIXED IND 330NH 4.7A 34 MOHM SMD	0
LQP03TNR22J02D TOKO / Murata	FIXED IND 220NH 60MA 13 OHM SMD	0
LQW15AN9N1G80D TOKO / Murata	FIXED IND 9.1NH 1.4A 80 MOHM SMD	0
LQW2BANR13J00L TOKO / Murata	FIXED IND 130NH 950MA 420 MOHM	735
LQW18ANR33J8ZD TOKO / Murata	FIXED IND 330NH 190MA 3.84 OHM	6929

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