Fixed Inductors

Part Number	Description / PDF	Quantity
LPS3015-184MRC COILCRAFT	SHIELDED POWER INDUCTORS 180H	1063
0402DC-7N1XGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 7.1NH	658
0402DC-9N2XGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 9.2NH	1355
0402DC-43NXGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 43.0NH	517
0603AF-111XJEW COILCRAFT	WIREWOUND INDUCTOR 110NH@7.9MHZ	6041
XPL2010-473MLC COILCRAFT	SHIELDED POWER INDUCTORS, 47UH	0
0402DC-9N0XJRW COILCRAFT	CERAMIC CHIP INDUCTORS, 9.0NH	1218
0603DC-43NXJRW COILCRAFT	CERAMIC CHIP INDUCTORS 43NH	4410
0402DC-1N7XJRW COILCRAFT	CERAMIC CHIP INDUCTORS, 1.7NH	1821
0402DC-12NXGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 12.0NH	9200
0603DC-30NXGRW COILCRAFT	CERAMIC CHIP INDUCTORS 30NH	4061
0402DC-1N8XJRW COILCRAFT	CERAMIC CHIP INDUCTORS, 1.8NH	1688
0603DC-20NXJRW COILCRAFT	CERAMIC CHIP INDUCTORS 20NH	2346
0603AF-68NXJEW COILCRAFT	WIREWOUND INDUCTOR 68NH@7.9MHZ	3450
0402DC-7N6XGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 7.6NH	1606
0402DC-6N7XGRW COILCRAFT	CERAMIC CHIP INDUCTORS, 6.7NH	811
0603DC-6N8XJRW COILCRAFT	CERAMIC CHIP INDUCTORS 6.8NH	7000
0402DC-56NXJRW COILCRAFT	CERAMIC CHIP INDUCTORS, 56.0NH	1042
0603DC-91NXGRW COILCRAFT	CERAMIC CHIP INDUCTORS 91NH	4115
0603DC-68NXJRW COILCRAFT	CERAMIC CHIP INDUCTORS 68NH	4442

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