Fixed Inductors

Part Number	Description / PDF	Quantity
HF1008R-561J API Delevan	FIXED IND 560NH 300MA 1.65 OHM	0
DC630R-562M API Delevan	FIXED IND 5.6UH 11.7A 7 MOHM TH	19
1025-90K API Delevan	FIXED IND 820UH 29MA 65 OHM TH	0
S1812R-392H API Delevan	FIXED IND 3.9UH 487MA 840 MOHM	0
5022-432H API Delevan	FIXED IND 4.3UH 390MA 2.4 OHM	0
5022R-913F API Delevan	FIXED IND 91UH 280MA 4.3 OHM SMD	0
P3519R-331J API Delevan	FIXED IND 330NH 3.97A 20 MOHM	0
1812R-271H API Delevan	FIXED IND 270NH 668MA 450 MOHM	0
SP1812-154H API Delevan	FIXED IND 150UH 198MA 5.1 OHM	0
1210R-681G API Delevan	FIXED IND 680NH 588MA 600 MOHM	0
1210R-221G API Delevan	FIXED IND 220NH 805MA 320 MOHM	0
SP1812R-184H API Delevan	FIXED IND 180UH 172MA 6.7 OHM	0
5022R-154F API Delevan	FIXED IND 150UH 237MA 6.05 OHM	0
1812R-221H API Delevan	FIXED IND 220NH 708MA 400 MOHM	0
SP1210R-473H API Delevan	FIXED IND 47UH 203MA 5 OHM SMD	0
P1330-823K API Delevan	FIXED IND 82UH 362MA 1.38 OHM	0
SP1210-332G API Delevan	FIXED IND 3.3UH 692MA 440 MOHM	0
SP1210R-682G API Delevan	FIXED IND 6.8UH 576MA 630 MOHM	0
S1210R-121J API Delevan	FIXED IND 120NH 1.062A 170 MOHM	0
5022-561F API Delevan	FIXED IND 560NH 1.645A 135 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