Fixed Inductors

Part Number	Description / PDF	Quantity
MLG0603P16NJT000 TDK Corporation	FIXED IND 16NH 200MA 1.2 OHM SMD	10188
1812R-153K API Delevan	FIXED IND 15UH 283MA 2.5 OHM SMD	0
0512CDMCCDS-2R2MC Sumida Corporation	FIXED IND 2.2UH 3.6A 72.6MOHM SM	465
SDR0805-271KL J.W. Miller / Bourns	FIXED IND 270UH 420MA 1.11OHM SM	366
LQP02HQ1N9C02L TOKO / Murata	FIXED IND 1.9NH 700MA 80 MOHM	0
VLS201610HBX-2R2M-1 TDK Corporation	FIXED IND 2.2UH 1.45A 170 MOHM	6251
SDR0403-1R4ML J.W. Miller / Bourns	FIXED IND 1.4UH 3.3A 38 MOHM SMD	9179
BRC2518T100M TAIYO YUDEN	FIXED IND 10UH 610MA 455 MOHM	0
ISC1812ES8R2J Vishay / Dale	FIXED IND 8.2UH 292MA 820 MOHM	0
LB2012T101K TAIYO YUDEN	FIXED IND 100UH 45MA 7 OHM SMD	14069
PM3316S-470M-RC J.W. Miller / Bourns	FIXED IND 47UH 1A 190 MOHM SMD	244
#B952AS-H-3R9N=P3 TOKO / Murata	FIXED IND 3.9UH 4.6A 18 MOHM SMD	64
7447709680 Würth Elektronik Midcom	FIXED IND 68UH 3.2A 89 MOHM SMD	0
L-15FR47JV4E Johanson Technology	FIXED IND 470NH 500MA 950 MOHM	0
HPL505032F1070MRD3P TDK Corporation	INDUCTORS FOR POWER CIRCUITS, AU	0
26S151C Murata Power Solutions	FIXED IND 150UH 850MA 400 MOHM	0
SP1210R-473G API Delevan	FIXED IND 47UH 203MA 5 OHM SMD	0
LQW2UASR10F0CL TOKO / Murata	FIXED IND 100NH 650MA 560 MOHM	1954
MIL1812-821K API Delevan	FIXED IND 820NH 354MA 1.6 OHM	1200
SDR7045-1R5M J.W. Miller / Bourns	FIXED IND 1.5UH 3.5A 27 MOHM SMD	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