Fixed Inductors

Part Number	Description / PDF	Quantity
SP1210R-823J API Delevan	FIXED IND 82UH 162MA 7.9 OHM SMD	0
S1008R-273K API Delevan	FIXED IND 27UH 160MA 7 OHM SMD	0
103-220KS API Delevan	FIXED IND 22NH 950MA 108 MOHM	0
5022-124H API Delevan	FIXED IND 120UH 255MA 5.2 OHM	0
0819-12G API Delevan	FIXED IND 330NH 460MA 490 MOHM	0
P3519-272K API Delevan	FIXED IND 2.7UH 1.85A 90 MOHM	0
1210R-682J API Delevan	FIXED IND 6.8UH 321MA 1.8 OHM	367
HRSPD127-104M API Delevan	FIXED IND 100UH 1.7A 182MOHM SMD	250
P1330-392K API Delevan	FIXED IND 3.9UH 1.39A 118 MOHM	0
S1210R-122K API Delevan	FIXED IND 1.2UH 574MA 490 MOHM	1148
8532-03K API Delevan	FIXED IND 1.5UH 5.67A 11 MOHM	0
2727-18J API Delevan	FIXED IND 270UH 90MA 24 OHM TH	0
1210R-823H API Delevan	FIXED IND 82UH 136MA 10 OHM SMD	0
P1812-123J API Delevan	FIXED IND 12UH 550MA 670 MOHM	0
8532R-48L API Delevan	FIXED IND 8.2MH 130MA 20.8 OHM	607
1812-120M API Delevan	FIXED IND 12NH 1.23A 100 MOHM	0
P1812-682H API Delevan	FIXED IND 6.8UH 600MA 472 MOHM	0
S1008R-121G API Delevan	FIXED IND 120NH 1.06A 100 MOHM	0
0819-86J API Delevan	FIXED IND 390UH 33MA 43 OHM TH	0
5022R-112H API Delevan	FIXED IND 1.1UH 930MA 420 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