Fixed Inductors

Part Number	Description / PDF	Quantity
LQW31HN8N8J03L TOKO / Murata	FIXED IND 8.8NH 750MA 29 MOHM	0
LQW15AN23NJ8ZD TOKO / Murata	FIXED IND 23NH 760MA 201 MOHM	6302
LQP02TN2N4B02D TOKO / Murata	FIXED IND 2.4NH 200MA 750 MOHM	0
1227AS-H-100M=P2 TOKO / Murata	FIXED IND 10UH 1.2A 204 MOHM SMD	706
DFE252010P-R33M=P2 TOKO / Murata	FIXED IND 330NH 3.8A 29 MOHM SMD	1601
LQH31MN3R9J03L TOKO / Murata	FIXED IND 3.9UH 125MA 1.5 OHM	0
MDH6045C-100MA=P3 TOKO / Murata	FIXED IND 10UH 1.9A 40MOHM SMD	901
LQH43MN221K03L TOKO / Murata	FIXED IND 220UH 110MA 5.4 OHM	0
LQW18ANR20G8ZD TOKO / Murata	FIXED IND 200NH 290MA 1.74 OHM	2037
LQP02HQ15NJ02E TOKO / Murata	FIXED IND 15NH 170MA 1.53 OHM	0
LQW15AN4N7B80D TOKO / Murata	FIXED IND 4.7NH 1.2A 71 MOHM SMD	6790
DFE2MCAHR24MJ0L TOKO / Murata	FIXED IND 240NH 4.2A 25 MOHM SMD	2470
LQW18AS18NJ0CD TOKO / Murata	FIXED IND 18NH 700MA 170 MOHM	0
LQW2BAN3N2J00L TOKO / Murata	FIXED IND 3.2NH 3.8A 20 MOHM	3074
LQH3NPN330MJRL TOKO / Murata	FIXED IND 33UH 280MA 948 MOHM	2083
MBH6045C-100MB=P3 TOKO / Murata	FIXED IND 10UH 2.5A 45.6 MOHM	0
LQP03TQ7N5H02D TOKO / Murata	FIXED IND 7.5NH 300MA 550 MOHM	12650
LQP03TG3N8B02D TOKO / Murata	FIXED IND 3.8NH 350MA 350 MOHM	0
LQP02HQ2N4C02L TOKO / Murata	FIXED IND 2.4NH 450MA 200 MOHM	0
LQH2HPN1R2NJRL TOKO / Murata	FIXED IND 1.2UH 1.24A 66 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