Fixed Inductors

Part Number	Description / PDF	Quantity
1210R-393G API Delevan	FIXED IND 39UH 170MA 6.4 OHM SMD	0
1210R-120K API Delevan	FIXED IND 12NH 931MA 140 MOHM	0
4426-10 API Delevan	FIXED IND 43NH 3A SMD	0
SP1210-153G API Delevan	FIXED IND 15UH 336MA 1.8 OHM SMD	0
DC780-122L API Delevan	FIXED IND 1.2UH 11.4A 3 MOHM TH	0
5022-181G API Delevan	FIXED IND 180NH 2.915A 43 MOHM	0
5022R-133F API Delevan	FIXED IND 13UH 520MA 1.2 OHM SMD	0
DC780R-472L API Delevan	FIXED IND 4.7UH 11.4A 5 MOHM TH	0
DC630R-123K API Delevan	FIXED IND 12UH 9.1A 11 MOHM TH	0
SP1812R-224J API Delevan	FIXED IND 220UH 164MA 7.5 OHM	0
SPD62R-333M API Delevan	FIXED IND 33UH 820MA 500 MOHM	1258
SP1008R-682K API Delevan	FIXED IND 6.8UH 282MA 1.43 OHM	0
2727-03G API Delevan	FIXED IND 15UH 360MA 1.5 OHM TH	0
SP1210R-332K API Delevan	FIXED IND 3.3UH 692MA 440 MOHM	96
SP1812-563G API Delevan	FIXED IND 56UH 323MA 1.9 OHM SMD	0
103-102J API Delevan	FIXED IND 1UH 425MA 540 MOHM SMD	0
1210-181H API Delevan	FIXED IND 180NH 860MA 280 MOHM	0
1812R-123J API Delevan	FIXED IND 12UH 317MA 2 OHM SMD	4888
P1330R-822K API Delevan	FIXED IND 8.2UH 1.02A 180 MOHM	0
8532-43H API Delevan	FIXED IND 3.3MH 230MA 6.56 OHM	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