Fixed Inductors

Part Number	Description / PDF	Quantity
LQW15AN4N7C00D TOKO / Murata	FIXED IND 4.7NH 750MA 70 MOHM	52593
LQH31MNR15K03L TOKO / Murata	FIXED IND 150NH 250MA 546 MOHM	0
LQH43NH270J03L TOKO / Murata	FIXED IND 27UH 280MA 720 MOHM	463
LQG15WH62NG02D TOKO / Murata	FIXED IND 62NH 180MA 1.9 OHM SMD	0
LQW2BHNR39J03L TOKO / Murata	FIXED IND 390NH 170MA 2.5 OHM	0
LQW15AW82NH80D TOKO / Murata	FIXED IND 82NH 370MA 870 MOHM	0
LQH5BPN470M38L TOKO / Murata	FIXED IND 47UH 1.1A 220 MOHM SMD	0
LQW18AN13NG8ZD TOKO / Murata	FIXED IND 13NH 1.5A 64 MOHM SMD	4690
LQW04CA60NK00D TOKO / Murata	FIXED IND 60NH 620MA 180 MOHM	4964
LQH43NN271J03L TOKO / Murata	FIXED IND 270UH 100MA 6.8 OHM	0
LQW04AN2N1C00D TOKO / Murata	FIXED IND 2.1NH 1.1A 30 MOHM	0
LQG15WH2N1B02D TOKO / Murata	FIXED IND 2.1NH 1A 60 MOHM SMD	0
LQW04AN3N6D00D TOKO / Murata	FIXED IND 3.6NH 530MA 100 MOHM	0
LQW31HN8N8K03L TOKO / Murata	FIXED IND 8.8NH 750MA 29 MOHM	0
LQW15AN9N3G8ZD TOKO / Murata	FIXED IND 9.3NH 1.4A 81 MOHM	9460
LQP03TN1N3C02D TOKO / Murata	FIXED IND 1.3NH 600MA 150 MOHM	14020
LQP02HQ5N1J02L TOKO / Murata	FIXED IND 5.1NH 350MA 350 MOHM	0
LQG15WZ91NJ02D TOKO / Murata	FIXED IND 91NH 160MA 2.3 OHM SMD	19950
LQM21PH1R0NGCD TOKO / Murata	FIXED IND 1UH 1A 130 MOHM SMD	340
LQP02HQ0N9C02L TOKO / Murata	FIXED IND 0.9NH 900MA 50 MOHM	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