Fixed Inductors

Part Number	Description / PDF	Quantity
LQP03HQ2N0B02D TOKO / Murata	FIXED IND 2NH 600MA 120 MOHM	26566
LQW18ANR27G8ZD TOKO / Murata	FIXED IND 270NH 260MA 2.42 OHM	3092
LQG15WH2N0S02D TOKO / Murata	FIXED IND 2NH 1A 50 MOHM SMD	0
LQB15NNR47J10D TOKO / Murata	FIXED IND 470NH 300MA 800 MOHM	36245
MDH12577C-100MA=P3 TOKO / Murata	FIXED IND 10UH 4.7A 14MOHM SMD	14
LQH3NPN150MJRL TOKO / Murata	FIXED IND 15UH 370MA 456 MOHM	68
LQH43PH3R3M26L TOKO / Murata	FIXED IND 3.3UH 2.1A 62.4 MOHM	1676
LQP03TG2N7B02D TOKO / Murata	FIXED IND 2.7NH 450MA 250 MOHM	3337
LQP15MN2N8W02D TOKO / Murata	FIXED IND 2.8NH 190MA 400 MOHM	4380
LQW15AN24NJ80D TOKO / Murata	FIXED IND 24NH 770MA 212 MOHM	0
LQP03TQ3N6B02D TOKO / Murata	FIXED IND 3.6NH 400MA 250 MOHM	13124
LQG15WH39NJ02D TOKO / Murata	FIXED IND 39NH 190MA 1.5 OHM SMD	9900
LQG15HH4N3C02D TOKO / Murata	FIXED IND 4.3NH 750MA 140 MOHM	9170
LQW15AN68NG0ZD TOKO / Murata	FIXED IND 68NH 140MA 1.96 OHM	8115
LQW2BASR12G00L TOKO / Murata	FIXED IND 120NH 400MA 510 MOHM	0
LQH2MCN220M52L TOKO / Murata	FIXED IND 22UH 130MA 7.15 OHM	0
LQW18AN4N2B80D TOKO / Murata	FIXED IND 4.2NH 220MA 28 MOHM	0
LQW18AN15NJ00D TOKO / Murata	FIXED IND 15NH 600MA 130 MOHM	24851
LQP02HQ3N9C02E TOKO / Murata	FIXED IND 3.9NH 350MA 350 MOHM	0
LQW15AN12NJ8ZD TOKO / Murata	FIXED IND 12NH 1.24A 93 MOHM	2621

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