Fixed Inductors

Part Number	Description / PDF	Quantity
LGJ12565TS-471MR70-H TDK Corporation	FIXED IND 470UH 750MA 770 MOHM	378
NLV25T-082J-EF TDK Corporation	FIXED IND 82NH 300MA 750 MOHM	0
SPM6545VT-470M-D TDK Corporation	FIXED IND 47UH 2.1A 229 MOHM SMD	849
MLG0603P2N1STD25 TDK Corporation	FIXED IND 2.1NH 600MA 100 MOHM	0
NLV32T-1R5J-PF TDK Corporation	FIXED IND 1.5UH 370MA 850 MOHM	8314
MLG0603P6N2ST000 TDK Corporation	FIXED IND 6.2NH 300MA 700 MOHM	22321
SPM5012T-6R8M-LR TDK Corporation	FIXED IND 6.8UH 1.6A 253 MOHM	618
VLS6045AF-6R8M TDK Corporation	FIXED IND 6.8UH 3.9A 37MOHM SMD	877
NLCV32T-R68M-EFRD TDK Corporation	FIXED IND 680NH 1.9A 54 MOHM SMD	911
MLP2016H1R0MT TDK Corporation	FIXED IND 1UH 1.3A 112.5 MOHM	0
NLV25T-R82J-PF TDK Corporation	FIXED IND 820NH 260MA 1 OHM SMD	5576
SLF7030T-330MR65-PF TDK Corporation	FIXED IND 33UH 650MA 160 MOHM	0
CLF12555T-4R7N-D TDK Corporation	FIXED IND 4.7UH 5.3A 15.2 MOHM	451
VLF403215MT-3R3M-CA TDK Corporation	FIXED IND 3.3UH 2.65A 62 MOHM	70
NLV32T-012J-EFD TDK Corporation	FIXED IND 12NH 450MA 140 MOHM	0
VLS3012ET-100M TDK Corporation	FIXED IND 10UH 640MA 336 MOHM	23515
MLZ2012M4R7HT000 TDK Corporation	FIXED IND 4.7UH 400MA 340 MOHM	6334
MHQ1005P3N5CT000 TDK Corporation	FIXED IND 3.5NH 900MA 90 MOHM	0
SPM3020T-4R7M TDK Corporation	FIXED IND 4.7UH 1.9A 173 MOHM	2874
MLG0603P5N6JT000 TDK Corporation	FIXED IND 5.6NH 350MA 400 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