Fixed Inductors

Part Number	Description / PDF	Quantity
LQH32MN560K23L TOKO / Murata	FIXED IND 56UH 85MA 4.9 OHM SMD	0
LQW15AN6N2C80D TOKO / Murata	FIXED IND 6.2NH 1.6A 56 MOHM SMD	0
LQW15AN9N1J00D TOKO / Murata	FIXED IND 9.1NH 540MA 140 MOHM	6704
LQM18NNR82K00D TOKO / Murata	FIXED IND 820NH 35MA 2.1 OHM SMD	5810
LQH32PB680MN0L TOKO / Murata	FIXED IND 68UH 275MA 2.74 OHM	0
LQP03TN22NH02D TOKO / Murata	FIXED IND 22NH 150MA 1.9 OHM SMD	29750
1235AS-H-6R8M=P3 TOKO / Murata	FIXED IND 6.8UH 1.9A 106 MOHM	1946
LQW18AN2N2D00D TOKO / Murata	FIXED IND 2.2NH 700MA 49 MOHM	7455
LQM18PN1R8NC0L TOKO / Murata	FIXED IND 1.8UH 700MA 300 MOHM	2814
LQG15HH22NG02D TOKO / Murata	FIXED INDUCTOR	0
LQP15MN3N3W02D TOKO / Murata	FIXED IND 3.3NH 190MA 400 MOHM	12619
LQG15WH22NJ02D TOKO / Murata	FIXED IND 22NH 230MA 1.1 OHM SMD	9940
LQH32NH330J23L TOKO / Murata	FIXED IND 33UH 175MA 1.368 OHM	1593
LQP02HQ2N5C02L TOKO / Murata	FIXED IND 2.5NH 450MA 200 MOHM	0
LQW15AN22NJ00D TOKO / Murata	FIXED IND 22NH 310MA 300 MOHM	34007
LQW18AS68NG00D TOKO / Murata	FIXED IND 68NH 600MA 340MOHM SMD	0
1155EA-0001=P3 TOKO / Murata	FIXED IND 10UH 3A 25 MOHM SMD	1
LQG15WZ24NH02D TOKO / Murata	FIXED IND 24NH 230MA 1.2 OHM SMD	0
LQH43MN390J03L TOKO / Murata	FIXED IND 39UH 240MA 1.4 OHM SMD	0
1217AS-H-6R8N=P3 TOKO / Murata	FIXED IND 6.8UH 4.8A 27.6 MOHM	53

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