Fixed Inductors

Part Number	Description / PDF	Quantity
SPM10040T-100M-HZ TDK Corporation	FIXED IND 10UH 8A 29.34MOHM SMD	789
MLG0402P1N8BT000 TDK Corporation	FIXED IND 1.8NH 200MA 600 MOHM	0
VLF504010MT-2R2M TDK Corporation	FIXED IND 2.2UH 2.65A 54 MOHM	0
MLJ1608WR15JT000 TDK Corporation	FIXED IND 150NH 700MA 160 MOHM	2889
MHQ1005P4N3ST000 TDK Corporation	FIXED IND 4.3NH 800MA 100 MOHM	13626
CLF12555T-220M-D TDK Corporation	FIXED IND 22UH 2.8A 51.6 MOHM	500
MLF2012E6R8MTD25 TDK Corporation	FIXED IND 6.8UH 15MA 650 MOHM	0
MLZ2012A2R2WT000 TDK Corporation	FIXED IND 2.2UH 650MA 150 MOHM	51
NLV25T-R56J-EFD TDK Corporation	FIXED IND 560NH 325MA 750 MOHM	0
NLV32T-R56J-PFD TDK Corporation	FIXED IND 560NH 450MA 550 MOHM	0
NLV25T-1R2J-EF TDK Corporation	FIXED IND 1.2UH 230MA 1.2 OHM	3178
VLS3010T-150MR55 TDK Corporation	FIXED IND 15UH 550MA 612 MOHM	415
SLF10165T-100M3R8-3PF TDK Corporation	FIXED IND 10UH 3.8A 22.2 MOHM	0
MLG0603SR18JTD25 TDK Corporation	FIXED IND 180NH 50MA 8.5 OHM SMD	0
NLFV32T-6R8M-EFT TDK Corporation	FIXED IND 6.8UH 260MA 204 MOHM	0
VLP4612T-1R0M1R5 TDK Corporation	FIXED IND 1UH 1.5A 110 MOHM SMD	7439
NLV25T-100J-PF TDK Corporation	FIXED IND 10UH 155MA 3.5 OHM SMD	596
NLCV32T-R15M-EFRD TDK Corporation	FIXED IND 150NH 2.6A 28.8 MOHM	1013
MLF1608DR56KTD25 TDK Corporation	FIXED IND 560NH 100MA 1.05 OHM	907
NLV32T-022J-EF TDK Corporation	FIXED IND 22NH 450MA 200 MOHM	2627

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