Fixed Inductors

Part Number	Description / PDF	Quantity
DR127-330-R PowerStor (Eaton)	FIXED IND 33UH 3.23A 60 MOHM SMD	5797
DR74-101-R PowerStor (Eaton)	FIXED IND 100UH 860MA 383 MOHM	3536
MCLA1005V2-221-R PowerStor (Eaton)	FIXED IND 220NH 100MA 4.0	0
DRAP125-R47-R PowerStor (Eaton)	FIXED IND 0.47UH 14.66A 3 MOHM	0
DRA125-221-R PowerStor (Eaton)	FIXED IND 220UH 1.142A 416 MOHM	95
HCM0503-R35-R PowerStor (Eaton)	FIXED IND 350NH 16.6A 4.29 MOHM	2897
HCM1A1104V2-R47-R PowerStor (Eaton)	FIXED IND 470NH 25A 1.27 MOHM	0
HCM1A0503V2-R20-R PowerStor (Eaton)	FIXED IND 200NH 20.5A 2 MOHM SMD	2000
HCM1A1707-1R5-R PowerStor (Eaton)	FIXED IND 1.5UH 25.5A 2.25 MOHM	0
HCM1104-R45-R PowerStor (Eaton)	FIXED IND 450NH 29A 1.23 MOHM	40
SD25-2R2-R PowerStor (Eaton)	FIXED IND 2.2UH 2.93A 31.1 MOHM	1330520300
FP1007R6-R39-R PowerStor (Eaton)	FIXED IND 390NH 61A 0.29 MOHM	0
HCPT1309-1R0-R PowerStor (Eaton)	FIXED IND 960NH 19.4A 1.9 MOHM	0
SD20-1R5-R PowerStor (Eaton)	FIXED IND 1.5UH 2.88A 31.2 MOHM	0
FP0805R1-R03-R PowerStor (Eaton)	FIXED IND 32NH 65A 0.17 MOHM SMD	0
HCM1A1305-1R0-R PowerStor (Eaton)	FIXED IND 1UH 22A 2.42MOHM SMD	165
MPI4020V2-1R0-R PowerStor (Eaton)	FIXED IND 1UH 6.5A 24 MOHM SMD	5420
DRA74-151-R PowerStor (Eaton)	FIXED IND 150UH 661MA 648 MOHM	1499
SD6020-6R2-R PowerStor (Eaton)	FIXED IND 6.2UH 1.63A 96 MOHM	0
WCL3225-391-R PowerStor (Eaton)	FIXED IND 390UH 45MA 21.5 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