Fixed Inductors

Part Number	Description / PDF	Quantity
MLF2012A1R0KTD25 TDK Corporation	FIXED IND 1UH 80MA 300 MOHM SMD	3066
MLG0603S3N9CTD25 TDK Corporation	FIXED IND 3.9NH 300MA 400 MOHM	0
RLF7030T-6R8M2R8-T TDK Corporation	FIXED IND 6.8UH 2.8A 44.76 MOHM	927
NLCV25T-R33M-EFRD TDK Corporation	FIXED IND 330NH 1.48A 78 MOHM	0
MLF1608C180KTD25 TDK Corporation	FIXED IND 18UH 2MA 1.6 OHM SMD	3099
VLS201612ET-R68N-CA TDK Corporation	FIXED IND 680NH 1.85A 72 MOHM	0
VLCF4018T-2R2N1R4-2 TDK Corporation	FIXED IND 2.2UH 1.44A 60 MOHM	2555
TFM322512ALMAR47MTAA TDK Corporation	INDUCTORS FOR POWER CIRCUITS, AU	1993
MLK0603L22NJT000 TDK Corporation	FIXED IND 22NH 100MA 1.6 OHM SMD	29328
SLF10165T-4R7N4R7-3PF TDK Corporation	FIXED IND 4.7UH 4.7A 15.2 MOHM	14
MLK0603L1N0ST000 TDK Corporation	FIXED IND 1NH 300MA 200 MOHM SMD	5974
MLG0603P1N8STD25 TDK Corporation	FIXED IND 1.8NH 700MA 100 MOHM	0
MLG1005S6N8JT000 TDK Corporation	FIXED IND 6.8NH 600MA 250 MOHM	29425
CLF10040T-100M-H TDK Corporation	FIXED IND 10UH 4A 26 MOHM SMD	1595
MLG0402P1N3BT000 TDK Corporation	FIXED IND 1.3NH 250MA 600 MOHM	0
MHQ1005P0N9BTD25 TDK Corporation	FIXED IND 0.9NH 1.2A 30 MOHM SMD	0
MLF2012C101MTD25 TDK Corporation	FIXED IND 100UH 2MA 3.1 OHM SMD	0
VLS252010HBU-220M TDK Corporation	FIXED IND 22UH 470MA 2.004 OHM	368
MLK0603L2N0ST000 TDK Corporation	FIXED IND 2NH 300MA 300 MOHM SMD	6686
MHQ1005PR56HT000 TDK Corporation	FIXED IND 560NH 70MA 10.6 OHM	9836

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