Fixed Inductors

Part Number	Description / PDF	Quantity
LQG15HZR12H02D TOKO / Murata	FIXED IND 120NH 200MA 1.3 OHM	7033
LQW2BANR20G00L TOKO / Murata	FIXED IND 200NH 750MA 630 MOHM	700
LQH32MN680K23L TOKO / Murata	FIXED IND 68UH 80MA 5.5 OHM SMD	1
LQG15HSR15J02D TOKO / Murata	FIXED IND 150NH 150MA 2.99 OHM	330
LQW18ASR27J0ZD TOKO / Murata	FIXED IND 270NH 170MA 2.3 OHM	6134
LQH32NH6R8J23L TOKO / Murata	FIXED IND 6.8UH 315MA 432 MOHM	1815
LQW18CAR21J00D TOKO / Murata	FIXED IND 210NH 1.05A 115 MOHM	3098
LQW04AN11NJ00D TOKO / Murata	FIXED IND 11NH 310MA 280 MOHM	0
LQG15WHR10H02D TOKO / Murata	FIXED IND 100NH 150MA 2.5 OHM	0
LQH43NN680J03L TOKO / Murata	FIXED IND 68UH 180MA 1.9 OHM SMD	229
LQG15HH6N2C02D TOKO / Murata	FIXED IND 6.2NH 600MA 200 MOHM	7007
LQH32DN331K23L TOKO / Murata	FIXED IND 330UH 60MA 13 OHM SMD	0
FDSD0630-H-1R5N=P3 TOKO / Murata	FIXED IND 1.5UH 8.5A 13 MOHM SMD	276
MDH12577C-221MA=P3 TOKO / Murata	FIXED IND 220UH 1.1A 250MOHM SMD	300
LQP02HQ3N9B02L TOKO / Murata	FIXED IND 3.9NH 350MA 350 MOHM	0
LQW15AN26NJ8ZD TOKO / Murata	FIXED IND 26NH 720MA 282 MOHM	9056
LQW15CAR80K00D TOKO / Murata	FIXED IND 800NH 190MA 2.1 OHM	7202
LQW15AN3N6C10D TOKO / Murata	FIXED IND 3.6NH 900MA 40 MOHM	5026
LQG15HS1N2C02D TOKO / Murata	FIXED IND 1.2NH 1A 70 MOHM SMD	522
LQH2MPN3R3MGRL TOKO / Murata	FIXED IND 3.3UH 640MA 564 MOHM	3134

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