Fixed Inductors

Part Number	Description / PDF	Quantity
LQP02HQ1N9C02L TOKO / Murata	FIXED IND 1.9NH 700MA 80 MOHM	0
#B952AS-H-3R9N=P3 TOKO / Murata	FIXED IND 3.9UH 4.6A 18 MOHM SMD	64
LQW2UASR10F0CL TOKO / Murata	FIXED IND 100NH 650MA 560 MOHM	1954
1225AS-H-100M=P2 TOKO / Murata	FIXED IND 10UH 850MA 300 MOHM	408
MDH10060C-471MA=P3 TOKO / Murata	FIXED IND 470UH 560MA 750 MOHM	465
LQW15AN3N5B80D TOKO / Murata	FIXED IND 3.5NH 1.95A 30 MOHM	0
LQW2UASR47J0CL TOKO / Murata	FIXED IND 470NH 470MA 1.19 OHM	1995
LQP03TG3N1B02D TOKO / Murata	FIXED IND 3.1NH 400MA 320 MOHM	0
LQW18AN4N9C80D TOKO / Murata	FIXED IND 4.9NH 1.2A 81 MOHM SMD	3689
LQW18AN19NJ80D TOKO / Murata	FIXED IND 19NH 1.4A 75 MOHM SMD	1095
LQW15AN2N2G8ZD TOKO / Murata	FIXED IND 2.2NH 2.53A 22 MOHM	354
DFEG7030D-220M=P3 TOKO / Murata	FIXED IND 22UH 1.9A 198 MOHM	0
LQH43PH100M26L TOKO / Murata	FIXED IND 10UH 1.17A 176.4 MOHM	483
LQP03TG2N7C02D TOKO / Murata	FIXED IND 2.7NH 450MA 250 MOHM	0
LQH32MN150J23L TOKO / Murata	FIXED IND 15UH 170MA 2.2 OHM SMD	1276
LQW15AN43NJ80D TOKO / Murata	FIXED IND 43NH 515MA 516 MOHM	0
LQB18NNR56N10D TOKO / Murata	FIXED IND 560NH 300MA 850 MOHM	0
LQW18AN18NG8ZD TOKO / Murata	FIXED IND 18NH 1.4A 75 MOHM SMD	143
LQW15AN1N8C00D TOKO / Murata	FIXED IND 1.8NH 460MA 160 MOHM	31823
LQW15AN8N6G8ZD TOKO / Murata	FIXED IND 8.6NH 1.42A 70 MOHM	11354

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