Fixed Inductors

Image	Part Number	Description / PDF	Quantity
	0402DC-7N7XGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 7.7NH	1872
	MPX1D0830L1R0 KEMET	FIXED IND 1UH 17.6A 5.7 MOHM SMD	824
	WCL3225-R82-R PowerStor (Eaton)	FIXED IND 820NH 450MA 300 MOHM	0
	LCCI0603S1N0GTAR Elco (AVX)	FIXED IND 1NH 1A 50 MOHM SMD	0
	MLG0603P13NHTD25 TDK Corporation	FIXED IND 13NH 250MA 1.1 OHM SMD	0
$L02012R7BHSTR\500$	L02012R7BHSTR\500 Elco (AVX)	FIXED IND 2.7NH 180MA 700 MOHM	3525
	AMDLA7030Q-4R7MT Abracon	FIXED IND 4.7UH 5A 33 MOHM SMD	1000
	AIML-1206-5R6K-T Abracon	FIXED IND 5.6UH 25MA 750 MOHM	0
	AISC-0402-4N3G-T Abracon	FIXED IND 4.3NH 700MA 91 MOHM	1694
	ASPI-0310FS-3R3M-T2 Abracon	FIXED IND 3.3UH 1.8A 130 MOHM	0
	HF1008R-151K API Delevan	FIXED IND 150NH 395MA 950 MOHM	0
	L0806B470JSWST KEMET	FIXED IND 47UH 120MA 3.9 OHM SMD	1825
	LQP02HQ0N4C02L TOKO / Murata	FIXED IND 0.4NH 1A 30MOHM SMD	0
	MLF2012C330MTD25 TDK Corporation	FIXED IND 33UH 5MA 1.1 OHM SMD	0
	MHQ1005PR11HTD25 TDK Corporation	FIXED IND 110NH 150MA 2.7 OHM	0
	0819-64G API Delevan	FIXED IND 47UH 76MA 8.2 OHM TH	0
	60B104C Murata Power Solutions	FIXED IND 100UH 7.5A 25 MOHM SMD	742
	SRR1208-682KL J.W. Miller / Bourns	FIXED IND 6.8MH 220MA 15.2OHM SM	0
	SRN8040TA-330M J.W. Miller / Bourns	FIXED IND 33UH 2.3A 100 MOHM SMD	11412
	PA4310.224NLT PulseLarsen Antenna	FIXED IND 220UH 2.5A 660 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