Fixed Inductors

Part Number	Description / PDF	Quantity
MLG1005S68NHT000 TDK Corporation	FIXED IND 68NH 200MA 1.5 OHM SMD	0
MHQ1005PR18GT000 TDK Corporation	FIXED IND 180NH 90MA 6 OHM SMD	2127
NLV32T-3R3J-EF TDK Corporation	FIXED IND 3.3UH 260MA 1.2 OHM	20965
MHQ1005P12NJT000 TDK Corporation	FIXED IND 12NH 450MA 240 MOHM	9728
MLF2012DR22JTD25 TDK Corporation	FIXED IND 220NH 250MA 300 MOHM	7664
VLCF5024T-2R7N1R5-2 TDK Corporation	FIXED IND 2.7UH 1.53A 31 MOHM	276
NLV25T-018J-PF TDK Corporation	FIXED IND 18NH 450MA 310 MOHM	0
MLG0603PR10JT000 TDK Corporation	FIXED IND 100NH 80MA 4.5 OHM SMD	13316
MLF1608D82NMTA00 TDK Corporation	FIXED IND 82NH 200MA 300 MOHM	10913
MLG1005S1N3CT000 TDK Corporation	FIXED IND 1.3NH 1A 100 MOHM SMD	9720
MLK1005S3N6STD25 TDK Corporation	FIXED IND 3.6NH 400MA 250 MOHM	9695
CLF12555T-331M-H TDK Corporation	FIXED IND 330UH 700MA 560 MOHM	238
MLG0603P27NHTD25 TDK Corporation	FIXED IND 27NH 140MA 2.1 OHM SMD	0
MLF2012D47NMTD25 TDK Corporation	FIXED IND 47NH 300MA 100 MOHM	2126
MLF1608DR15JTD25 TDK Corporation	FIXED IND 150NH 200MA 450 MOHM	3515
MLZ2012M6R8HT000 TDK Corporation	FIXED IND 6.8UH 350MA 400 MOHM	15909
NLV32T-033J-PFD TDK Corporation	FIXED IND 33NH 450MA 240 MOHM	0
VLBU10060120T-R12L-1 TDK Corporation	FIXED IND 120NH 83A 0.12 MOHM	175
MLG0603P5N6HTD25 TDK Corporation	FIXED IND 5.6NH 350MA 400 MOHM	0
SPM4020T-3R3M-CA TDK Corporation	FIXED IND 3.3UH 2.4A 123 MOHM	839

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