Fixed Inductors

Part Number	Description / PDF	Quantity
B82477P4684M000 TDK EPCOS	FIXED IND 680UH 690MA 1.05 OHM	235
UP2B-1R0-R PowerStor (Eaton)	FIXED IND 1UH 9.3A 6.5 MOHM SMD	0
HTPT66-122K API Delevan	FIXED IND 1.2UH 15.3A 2.9 MOHM	0
AISC-0402HP-3N6J-T Abracon	FIXED IND 3.6NH 1.7A 45 MOHM SMD	0
ISC1210SY180K Vishay / Dale	FIXED IND 18UH 155MA 2.7 OHM SMD	0
NRS5010T100MMGF TAIYO YUDEN	FIXED IND 10UH 950MA 300 MOHM	1623
CTX150-5-52-R PowerStor (Eaton)	FIXED IND 150UH 7.7A 40.1 MOHM	6
SRP0310-1R0K J.W. Miller / Bourns	FIXED IND 1UH 3.4A 58.5 MOHM SMD	160
VLCF4024T-100MR90-2 TDK Corporation	FIXED IND 10UH 900MA 136 MOHM	2955
SRR7045-390M J.W. Miller / Bourns	FIXED IND 39UH 1.1A 130 MOHM SMD	0
LQG15WZ40NH02D TOKO / Murata	FIXED IND 40NH 190MA 1.5 OHM SMD	0
8532R-29K API Delevan	FIXED IND 220UH 840MA 505 MOHM	0
74458010 Würth Elektronik Midcom	FIXED IND 10UH 4.3A 31 MOHM SMD	0
HK212522NJ-T TAIYO YUDEN	FIXED IND 22NH 300MA 500 MOHM	4029
IHLP1212BZEVR22M5A Vishay / Dale	FIXED IND 0.22 UH 8.83A 13.74 MO	0
SRP5015TA-6R8M J.W. Miller / Bourns	FIXED IND 6.8UH 2.3A 171MOHM SMD	19
AMPLA4020Q-R36MT Abracon	FIXED IND 360NH 9A 12 MOHM SMD	0
0805CS-821EGTS Delta Electronics	FIXED IND 820NH 180MA 2.35 OHM	3402
AISC-0603F-R24J-T Abracon	FIXED IND 240NH 690MA 170 MOHM	0
LQG15WZ2N8C02D TOKO / Murata	FIXED IND 2.8NH 900MA 80 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