Fixed Inductors

Part Number	Description / PDF	Quantity
MLF2012DR12JTD25 TDK Corporation	FIXED IND 120NH 300MA 200 MOHM	1618
VLS6045AF-3R3N TDK Corporation	FIXED IND 3.3UH 5A 22MOHM SMD	2270
MLF1608DR10KTA00 TDK Corporation	FIXED IND 100NH 200MA 350 MOHM	3930
NLV32T-047J-EF TDK Corporation	FIXED IND 47NH 450MA 300 MOHM	1100
MHQ1005PR20GT000 TDK Corporation	FIXED IND 200NH 80MA 6.2 OHM SMD	9648
MLK1005S1N1STD25 TDK Corporation	FIXED IND 1.1NH 500MA 120 MOHM	9694
MLZ1608DR10DT000 TDK Corporation	FIXED IND 100NH 850MA 140 MOHM	53809
MLG0603S39NJTD25 TDK Corporation	FIXED IND 39NH 50MA 2 OHM SMD	10380
VLF252010MT-6R8M TDK Corporation	FIXED IND 6.8UH 850MA 360 MOHM	0
MLG1608SR33JT000 TDK Corporation	FIXED IND 330NH 100MA 2.8 OHM	13700
NLV25T-012J-EF TDK Corporation	FIXED IND 12NH 500MA 270 MOHM	1970
NLV32T-8R2J-PF TDK Corporation	FIXED IND 8.2UH 170MA 2 OHM SMD	1850
RLF7045T-330M1R2-D TDK Corporation	FIXED IND 33UH 1.2A 150 MOHM SMD	994
CLF6045T-1R0N-D TDK Corporation	FIXED IND 1UH 4.5A 14.3 MOHM SMD	3788
VLS252010CX-1R0M TDK Corporation	FIXED IND 1UH 2.29A 65M OHM SMD	0
MLG0603S3N0CT000 TDK Corporation	FIXED IND 3NH 300MA 300 MOHM SMD	0
VLS3012T-470MR34 TDK Corporation	FIXED IND 47UH 340MA 1.512 OHM	3727
MLG0603P0N7CT000 TDK Corporation	FIXED IND 0.7NH 1A 60 MOHM SMD	18973
VLF302512MT-100M TDK Corporation	FIXED IND 10UH 950MA 299 MOHM	0
MLF1608DR10JT000 TDK Corporation	FIXED IND 100NH 200MA 350 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