Fixed Inductors

Part Number	Description / PDF	Quantity
LQW2BAN20NG00L TOKO / Murata	FIXED IND 20NH 2.2A 50 MOHM SMD	2497
LQH31HNR29K03L TOKO / Murata	FIXED IND 290NH 420MA 221 MOHM	0
DFE252010F-3R3M=P2 TOKO / Murata	FIXED IND 3.3UH 1.6A 170 MOHM	2566
LQP02HQ4N3J02L TOKO / Murata	FIXED IND 4.3NH 350MA 350 MOHM	0
LQH3NPN4R7MJRL TOKO / Murata	FIXED IND 4.7UH 710MA 144 MOHM	5588
LQP03TQ4N7J02D TOKO / Murata	FIXED IND 4.7NH 350MA 350 MOHM	7362
LQH31HNR88J03L TOKO / Murata	FIXED IND 880NH 180MA 1.118 OHM	565
LQW2BASR22J00L TOKO / Murata	FIXED IND 220NH 400MA 700 MOHM	7240
LQH2MPN1R0NGRL TOKO / Murata	FIXED IND 1UH 900MA 300 MOHM	2802
LQW2UASR62J00L TOKO / Murata	FIXED IND 620NH 300MA 1.4 OHM	2000
LQG15HN1N5C02D TOKO / Murata	FIXED IND 1.5NH 1A 80 MOHM SMD	7572
LQP03HQ3N7B02D TOKO / Murata	FIXED IND 3.7NH 500MA 170 MOHM	7744
LQH2HPN1R0MDRL TOKO / Murata	FIXED IND 1UH 960MA 288 MOHM SMD	2315
LQW15AN56NG8ZD TOKO / Murata	FIXED IND 56NH 340MA 996 MOHM	0
LQW18AN27NG10D TOKO / Murata	FIXED IND 27NH 590MA 116 MOHM	27206
LQW18AN20NG00D TOKO / Murata	FIXED IND 20NH 550MA 160 MOHM	10232
LQH32PN470MN0L TOKO / Murata	FIXED IND 47UH 310MA 2.14 OHM	1474
LQW18AS56NJ0ZD TOKO / Murata	FIXED IND 56NH 600MA 310 MOHM	1263
LQW18ANR15J00D TOKO / Murata	FIXED IND 150NH 160MA 1.5 OHM	936
LQH43NN271K03L TOKO / Murata	FIXED IND 270UH 100MA 6.8 OHM	0

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