Fixed Inductors

Part Number	Description / PDF	Quantity
MLG0603Q0N4C TDK Corporation	FIXED IND 0.4NH 600MA 100 MOHM	14845
VLS3015ET-3R3M-CA TDK Corporation	FIXED IND 3.3UH 1.5A 112 MOHM	1750
VLS6045EX-1R0N-CA TDK Corporation	FIXED IND 1UH 6A 15.6MOHM SMD	1348
MLP2520W1R5MT0S1 TDK Corporation	FIXED IND 1.5UH 1.8A 98 MOHM SMD	529
MHQ0402PSA8N2JT000 TDK Corporation	FIXED IND 8.2NH 180MA 1.2 OHM	0
MLG0603P2N0CT000 TDK Corporation	FIXED IND 2NH 600MA 100 MOHM SMD	10749
NLFV32T-330K-EFT TDK Corporation	FIXED IND 33UH 95MA 780 MOHM SMD	0
MLG0402Q1N5CT000 TDK Corporation	FIXED IND 1.5NH 220MA 600 MOHM	0
NLV25T-033J-PFD TDK Corporation	FIXED IND 33NH 400MA 420 MOHM	0
MLG0603S1N1BT000 TDK Corporation	FIXED IND 1.1NH 550MA 150 MOHM	0
LTF5022T-1R8N3R6-LC TDK Corporation	FIXED IND 1.8UH 3.8A 32 MOHM SMD	0
MLF2012DR56KTD25 TDK Corporation	FIXED IND 560NH 150MA 550 MOHM	302
MLF2012DR33JT000 TDK Corporation	FIXED IND 330NH 250MA 400 MOHM	3706
VLS252010CX-R68M TDK Corporation	FIXED IND 680NH 2.62A 50 MOHM	0
NL453232T-680J-PF TDK Corporation	FIXED IND 68UH 130MA 6 OHM SMD	1304
LTF4022T-2R2N-D TDK Corporation	FIXED IND 2.2UH 2.6A 41 MOHM SMD	92
MLF2012E5R6MTD25 TDK Corporation	FIXED IND 5.6UH 15MA 600 MOHM	0
CLF6045NIT-680M-D TDK Corporation	FIXED IND 68UH 810MA 240MOHM SMD	3971
SPM12565VT-2R2M-D TDK Corporation	FIXED IND 2.2UH 20.2A 3.4 MOHM	429
MHQ0603P2N1BTD25 TDK Corporation	FIXED IND 2.1NH 700MA 150 MOHM	4000

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