Fixed Inductors

Part Number	Description / PDF	Quantity
MPIA4020V2-4R7-R PowerStor (Eaton)	FIXED IND 4.7UH 2.7A 118 MOHM	1180
MCL1608V1-R82-R PowerStor (Eaton)	FIXED IND 820NH 100MA 600 MOHM	0
SD20-4R7-R PowerStor (Eaton)	FIXED IND 4.7UH 2.05A 61.2 MOHM	139
DR1040-100-R PowerStor (Eaton)	FIXED IND 10UH 3.8A 35 MOHM SMD	4211
SD3112-220-R PowerStor (Eaton)	FIXED IND 22UH 370MA 953 MOHM	0
CTX50-5-52M-R PowerStor (Eaton)	FIXED IND 50UH 7.6A 24.8 MOHM TH	0
FP1007R6-R47-R PowerStor (Eaton)	FIXED IND 470NH 61A 0.29 MOHM	780
CTX10-2-52M-R PowerStor (Eaton)	FIXED IND 10UH 4.7A 18.3 MOHM TH	0
DRA73-3R3-R PowerStor (Eaton)	FIXED IND 3.3UH 3.59A 22 MOHM	968
HC1-7R8-R PowerStor (Eaton)	FIXED IND 7.8UH 12.79A 5.7 MOHM	250
HCM0503-1R5-R PowerStor (Eaton)	FIXED IND 1.5UH 7.5A 19 MOHM SMD	0
DR1040-2R5-R PowerStor (Eaton)	FIXED IND 2.5UH 6.1A 9 MOHM SMD	0
HCM0703-8R2-R PowerStor (Eaton)	FIXED IND 8.2UH 4A 68 MOHM SMD	1802
MCLA2012V1-R082-R PowerStor (Eaton)	FIXED IND 0.082UH 300MA 0.2	0
SD3112-221-R PowerStor (Eaton)	FIXED IND 220UH 121MA 9.12 OHM	0
MCL2012V1-R082-R PowerStor (Eaton)	FIXED IND 82NH 350MA 200 MOHM	0
UP2-680-R PowerStor (Eaton)	FIXED IND 68UH 1.7A 189.8 MOHM	0
SD53-220-R PowerStor (Eaton)	FIXED IND 22UH 810MA 208 MOHM	2856
WCL2520-470-R PowerStor (Eaton)	FIXED IND 47UH 60MA 5.7 OHM SMD	3755
DR73-820-R PowerStor (Eaton)	FIXED IND 82UH 860MA 384 MOHM	716

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