Fixed Inductors

Part Number	Description / PDF	Quantity
VLF403215MT-1R0N TDK Corporation	FIXED IND 1UH 3.56A 31 MOHM SMD	230
NLV32T-R82J-PFD TDK Corporation	FIXED IND 820NH 450MA 650 MOHM	0
CLF10040T-680M-H TDK Corporation	FIXED IND 68UH 1.6A 180 MOHM SMD	1487
MHQ1005P2N2BT000 TDK Corporation	FIXED IND 2.2NH 1A 60 MOHM SMD	0
VLS252010ET-1R0N TDK Corporation	FIXED IND 1UH 1.75A 84 MOHM SMD	84913
SLF7045T-6R8M1R9-H TDK Corporation	FIXED IND 6.8UH 1.9A 46.8 MOHM	0
SLF7045T-680MR75-H TDK Corporation	FIXED IND 68UH 750MA 324 MOHM	1560
MLF1608E5R6KTD25 TDK Corporation	FIXED IND 5.6UH 15MA 1.1 OHM SMD	3555
VLS4012CX-150M-1 TDK Corporation	FIXED INDUCTOR 15UH SMD	990
MLF2012E6R8MT TDK Corporation	FIXED IND 6.8UH 15MA 650 MOHM	0
MHQ1005P2N6BTD25 TDK Corporation	FIXED IND 2.6NH 900MA 70 MOHM	0
MLG0603P10NJTD25 TDK Corporation	FIXED IND 10NH 250MA 950 MOHM	12678
SPM3012T-R47M-CA02 TDK Corporation	FIXED IND 470NH 4.5A 34.8 MOHM	0
VLS252012HBX-R33M-1 TDK Corporation	FIXED IND 330NH 5.25A 31 MOHM	1116
CLF6045T-220M-D TDK Corporation	FIXED IND 22UH 1.7A 93.6 MOHM	967
MHQ1005P30NHT000 TDK Corporation	FIXED IND 30NH 220MA 1.3 OHM SMD	0
MLF1608A1R5MTD25 TDK Corporation	FIXED IND 1.5UH 50MA 700 MOHM	3825
NLC565050T-8R2K-PF TDK Corporation	FIXED IND 8.2UH 750MA 180 MOHM	83
MHQ1005P1N0ST000 TDK Corporation	FIXED IND 1NH 1.2A 30 MOHM SMD	14686
NLV25T-R68J-PF TDK Corporation	FIXED IND 680NH 300MA 850 MOHM	3440

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