Fixed Inductors

Part Number	Description / PDF	Quantity
MLF1608A2R2M TDK Corporation	FIXED IND 2.2UH 30MA 1 OHM SMD	501
MLG0603P13NHTD25 TDK Corporation	FIXED IND 13NH 250MA 1.1 OHM SMD	0
MLF2012C330MTD25 TDK Corporation	FIXED IND 33UH 5MA 1.1 OHM SMD	0
MHQ1005PR11HTD25 TDK Corporation	FIXED IND 110NH 150MA 2.7 OHM	0
VLCF4028T-470MR48-2 TDK Corporation	FIXED IND 47UH 480MA 490 MOHM	359
SPM3020T-R47M-LR TDK Corporation	FIXED IND 470NH 4.8A 22.7 MOHM	5761
MHQ1005P30NHTD25 TDK Corporation	FIXED IND 30NH 220MA 1.3 OHM SMD	0
VLF302512MT-3R3M-CA TDK Corporation	FIXED IND 3.3UH 1.63A 108 MOHM	18
MLZ1608DR47DT000 TDK Corporation	FIXED IND 470NH 500MA 420 MOHM	21686
MLG1608B1N2ST000 TDK Corporation	FIXED IND 1.2NH 600MA 100 MOHM	535
MLG0603P3N9CT000 TDK Corporation	FIXED IND 3.9NH 400MA 300 MOHM	3961
MLG0603P1N1STD25 TDK Corporation	FIXED IND 1.1NH 1A 70 MOHM SMD	0
MHQ0603P0N8CT000 TDK Corporation	FIXED IND 0.8NH 1A 70 MOHM SMD	20004
MHQ1005P68NHTD25 TDK Corporation	FIXED IND 68NH 160MA 2 OHM SMD	0
SPM10065VT-470M-D TDK Corporation	FIXED IND 47UH 4A 79.8 MOHM SMD	729
MLG1005S8N2JTD25 TDK Corporation	FIXED IND 8.2NH 500MA 300 MOHM	10760
NLV32T-R39J-PFD TDK Corporation	FIXED IND 390NH 450MA 450 MOHM	0
MLZ2012M100WT000 TDK Corporation	FIXED IND 10UH 350MA 470 MOHM	130118
VLF252012MT-1R5N-CA TDK Corporation	FIXED IND 1.5UH 2.17A 69 MOHM	0
MLF2012K560KT000 TDK Corporation	FIXED IND 56UH 4MA 2.8 OHM SMD	5555

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