Fixed Inductors

Part Number	Description / PDF	Quantity
SBC4-470-162 KEMET	FIXED IND 47UH 1.6A 110 MOHM TH	1425
MHQ0603P0N8CT000 TDK Corporation	FIXED IND 0.8NH 1A 70 MOHM SMD	20004
SDR2207-390KL J.W. Miller / Bourns	FIXED IND 39UH 3.2A 65 MOHM SMD	0
MPL-AT2010-R47 MPS (Monolithic Power Systems)	FIXED IND 470NH 4.4A 27 MOHM SMD	2990
LQG15WH2N2S02D TOKO / Murata	FIXED IND 2.2NH 1A 60 MOHM SMD	8414
IHLP2525EZERR22M01 Vishay / Dale	FIXED IND 220NH SMD	0
IMC1210EB6R8J Vishay / Dale	FIXED IND 6.8UH 204MA 1.8 OHM	0
MHQ1005P68NHTD25 TDK Corporation	FIXED IND 68NH 160MA 2 OHM SMD	0
IHDM1008BCEV1R2M30 Vishay / Dale	FIXED IND 1.2UH 80A 0.3 MOHM TH	487
0402HM-5N1ECTS Delta Electronics	FIXED IND 5.1NH 600MA 120 MOHM	7990
SPM10065VT-470M-D TDK Corporation	FIXED IND 47UH 4A 79.8 MOHM SMD	729
SP1812R-124G API Delevan	FIXED IND 120UH 210MA 4.6 OHM	0
SBCP-47HY150B KEMET	FIXED IND 15UH 1.25A 87 MOHM TH	590
LQH3NPZ101MMEL TOKO / Murata	FIXED IND 100UH 270MA 1.908 OHM	1564
WCL3225-R12-R PowerStor (Eaton)	FIXED IND 120NH 450MA 200 MOHM	0
SRU6013-470Y J.W. Miller / Bourns	FIXED IND 47UH 660MA 675MOHM SMD	0
5022-133G API Delevan	FIXED IND 13UH 520MA 1.2 OHM SMD	0
B82422A3331K100 TDK EPCOS	FIXED IND 330NH 200MA 1.3 OHM	1326
HCMA0703-R22-R PowerStor (Eaton)	FIXED IND 220NH 23A 2.8 MOHM SMD	1140
S1812R-683F API Delevan	FIXED IND 68UH 215MA 4.3 OHM 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