Fixed Inductors

Part Number	Description / PDF	Quantity
103-472JS API Delevan	FIXED IND 4.7UH 230MA 1.8 OHM	0
1812-561K API Delevan	FIXED IND 560NH 409MA 1.2 OHM	0
1210-100K API Delevan	FIXED IND 10NH 966MA 130 MOHM	0
4590-562K API Delevan	FIXED IND 5.6UH 7.77A 11 MOHM TH	0
S1210-153H API Delevan	FIXED IND 15UH 254MA 2.5 OHM SMD	0
P3519R-823J API Delevan	FIXED IND 82UH 387MA 1.96 OHM	100
SP1812R-563K API Delevan	FIXED IND 56UH 323MA 1.9 OHM SMD	0
S1210R-332J API Delevan	FIXED IND 3.3UH 449MA 800 MOHM	0
1210-180J API Delevan	FIXED IND 18NH 821MA 180 MOHM	0
SDS680R-685M API Delevan	FIXED IND 6.8MH 40MA 25 OHM SMD	3057
P1812-332K API Delevan	FIXED IND 3.3UH 750MA 323 MOHM	0
1641-102K API Delevan	FIXED IND 1UH 1.09A 70 MOHM TH	811
8532-19H API Delevan	FIXED IND 33UH 2.17A 75 MOHM SMD	0
5022-224J API Delevan	FIXED IND 220UH 213MA 7.45 OHM	0
1008R-100K API Delevan	FIXED IND 10NH 1.562A 50 MOHM	998
1812R-223K API Delevan	FIXED IND 22UH 250MA 3.2 OHM SMD	0
SDS850R-105M API Delevan	FIXED IND 1MH 150MA 5 OHM SMD	0
S1812R-332K API Delevan	FIXED IND 3.3UH 534MA 700 MOHM	0
5022-242G API Delevan	FIXED IND 2.4UH 575MA 1.1 OHM	0
5022R-114H API Delevan	FIXED IND 110UH 262MA 4.9 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