Fixed Inductors

Part Number	Description / PDF	Quantity
IMC1210EBR39K Vishay / Dale	FIXED IND 390NH 450MA 450 MOHM	0
LQP02TN2N2C02D TOKO / Murata	FIXED IND 2.2NH 200MA 750 MOHM	0
B82432T1333K000 TDK EPCOS	FIXED IND 33UH 400MA 1.2 OHM SMD	3164
SP1210-471H API Delevan	FIXED IND 470NH 1.44A 100 MOHM	0
LQW03AW4N7J00D TOKO / Murata	FIXED IND 4.7NH 620MA 90 MOHM	8133
TYA3015220M-10 Laird - Performance Materials	FIXED IND 22UH 560MA 910 MOHM	9954
L-07W9N5KV4T Johanson Technology	FIXED IND 9.5NH 680MA 200 MOHM	0
S1812R-473F API Delevan	FIXED IND 47UH 242MA 3.4 OHM SMD	0
SPM6530T-R47M-HZ TDK Corporation	FIXED IND 470NH 20.5A 3.63 MOHM	1550
SDR0403-561KL J.W. Miller / Bourns	FIXED IND 560UH 120MA 7.8OHM SMD	1900
L0603B100MPWFT KEMET	FIXED IND 10UH 200MA 1.2 OHM SMD	17
LQW04AN6N2C00D TOKO / Murata	FIXED IND 6.2NH 390MA 190 MOHM	0
SRU5011-680Y J.W. Miller / Bourns	FIXED IND 68UH 260MA 1.24OHM SMD	0
LQW15AN5N6D10D TOKO / Murata	FIXED IND 5.6NH 800MA 51 MOHM	5823
LQW18AS39NG0ZD TOKO / Murata	FIXED IND 39NH 600MA 250 MOHM	689
ER1641-102KS API Delevan	FIXED IND 1UH 1.07A 70 MOHM TH	0
SBC6-100-462 KEMET	FIXED IND 10UH 4.6A 30 MOHM TH	1573
AMPLA4012Q-1R0MT Abracon	FIXED IND 1UH 4A 47 MOHM SMD	0
0402HM-270EGTS Delta Electronics	FIXED IND 27NH 280MA 520 MOHM	7168
74455115 Würth Elektronik Midcom	FIXED IND 15UH 1.1A 230 MOHM SMD	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