Fixed Inductors

Part Number	Description / PDF	Quantity
FP4-120-R PowerStor (Eaton)	FIXED IND 120NH 40A 0.65 MOHM	0
DRA127-4R7-R PowerStor (Eaton)	FIXED IND 4.7UH 8.14A 9.4 MOHM	22
FP2-V100-R PowerStor (Eaton)	FIXED IND 100NH 37A 0.28 MOHM	750
HCMA0703-R15-R PowerStor (Eaton)	FIXED IND 150NH 26A 2.5 MOHM SMD	7
HCMA1104-R36-R PowerStor (Eaton)	FIXED IND 360NH 30A 1.2 MOHM SMD	662
MCL1608V2-470-R PowerStor (Eaton)	FIXED IND 47NH 300MA 700 MOHM	7930
HCM1A0503-R35-R PowerStor (Eaton)	FIXED IND 350NH 11.8A 4.3 MOHM	0
DRA125-1R5-R PowerStor (Eaton)	FIXED IND 1.5UH 12.89A 3.3 MOHM	0
DR125-102-R PowerStor (Eaton)	FIXED IND 1MH 570MA 1.69 OHM SMD	737
HCM1A1104-R20-R PowerStor (Eaton)	FIXED IND 200NH 33A 0.72MOHM SMD	0
FP0705R1-R18-R PowerStor (Eaton)	FIXED IND 180NH 43A 0.25 MOHM	0
DRA125-101-R PowerStor (Eaton)	FIXED IND 100UH 1.745A 178 MOHM	141
HCM1A1707V2-150-R PowerStor (Eaton)	FIXED IND 15UH 11.8A 15.5 MOHM	98
UP4B-221-R PowerStor (Eaton)	FIXED IND 220UH 1.4A 357.1 MOHM	496
UP2-820-R PowerStor (Eaton)	FIXED IND 82UH 1.5A 247.3 MOHM	0
FP2-S100-R PowerStor (Eaton)	FIXED IND 100NH 39A 0.24 MOHM	1696
SD14-4R5-R PowerStor (Eaton)	FIXED IND 4.5UH 1.64A 93.5 MOHM	0
HCM1A1307-8R2-R PowerStor (Eaton)	FIXED IND 8.2UH 8.2A 13MOHM SMD	0
HCMA1104-4R7-R PowerStor (Eaton)	FIXED IND 4.7UH 8.5A 20 MOHM SMD	0
MCL2012V2-271-R PowerStor (Eaton)	FIXED IND 270NH 300MA 1.8 OHM	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