Fixed Inductors

Part Number	Description / PDF	Quantity
1248AS-H-100M=P3 TOKO / Murata	FIXED IND 10UH 3.4A 52.8 MOHM	208
LQM18DN6R8M70L TOKO / Murata	FIXED IND 6.8UH 330MA NONAUTOMUL	7505
LQH44NN2R2M03L TOKO / Murata	FIXED IND 2.2UH 2.5A 22.8 MOHM	0
LQW15AN11NJ80D TOKO / Murata	FIXED IND 11NH 1.4A 83 MOHM SMD	0
LQW18AN73NG8ZD TOKO / Murata	FIXED IND 73NH 590MA 410 MOHM	3532
LQH55DN2R2M03L TOKO / Murata	FIXED IND 2.2UH 3.2A 40.6 MOHM	23
LQH32CN220K23L TOKO / Murata	FIXED IND 22UH 250MA 923 MOHM	547
LQW15AN4N9D8ZD TOKO / Murata	FIXED IND 4.9NH 1.2A 71 MOHM	0
LQP03TQ13NH02D TOKO / Murata	FIXED IND 13NH 250MA 690 MOHM	3881
LQW15CNR47K1ZD TOKO / Murata	FIXED IND 470NH 350MA 660 MOHM	2052
LQP02HQ1N6B02L TOKO / Murata	FIXED IND 1.6NH 700MA 80 MOHM	0
LQM21DH100M70L TOKO / Murata	FIXED IND 10UH 300MA 845 MOHM	2672
LQP18MN6N8C02D TOKO / Murata	FIXED IND 6.8NH 200MA 700 MOHM	3990
LQH32MN561K23L TOKO / Murata	FIXED IND 560UH 40MA 28 OHM SMD	2156
LQW15AN4N4D8ZD TOKO / Murata	FIXED IND 4.4NH 1.6A 52 MOHM	0
LQG15HS1N6B02D TOKO / Murata	FIXED INDUCTOR 1.6NH 0402	10000
LQW18AN8N7G8ZD TOKO / Murata	FIXED IND 8.7NH 1.6A 52 MOHM	2344
LQW15AN5N2C8ZD TOKO / Murata	FIXED IND 5.2NH 1.77A 40 MOHM	9396
LQW18AN23NG8ZD TOKO / Murata	FIXED IND 23NH 1.3A 86 MOHM SMD	7373
LQW2BASR15J00L TOKO / Murata	FIXED IND 150NH 400MA 560 MOHM	499

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