Fixed Inductors

Part Number	Description / PDF	Quantity
84153C Murata Power Solutions	FIXED IND 15UH 750MA 450 MOHM	2101
1422509C Murata Power Solutions	FIXED IND 2.2MH 900MA 1 OHM TH	1173
22R153MC Murata Power Solutions	FIXED IND 15UH 2.08A 70 MOHM SMD	0
12LRS682C Murata Power Solutions	FIXED IND 6.8UH 4.7A 20 MOHM TH	0
48330SC Murata Power Solutions	FIXED IND 33UH 2.8A 73 MOHM SMD	0
33220C Murata Power Solutions	FIXED IND 22UH 5.1A 33 MOHM TH	10
1468431C Murata Power Solutions	FIXED IND 680UH 3.1A 173 MOHM	2
37951C Murata Power Solutions	FIXED IND 950NH 18A 1.3 MOHM SMD	0
18R106C Murata Power Solutions	FIXED IND 10MH 130MA 12 OHM TH	200
19R335C Murata Power Solutions	FIXED IND 3.3MH 420MA 2.5 OHM TH	0
23S270C Murata Power Solutions	FIXED IND 27UH 720MA 218 MOHM	0
15223C Murata Power Solutions	FIXED IND 22UH 6.8A 18.8 MOHM	0
12LRS103C Murata Power Solutions	FIXED IND 10UH 3.4A 50 MOHM TH	0
28334C Murata Power Solutions	FIXED IND 330UH 950MA 575 MOHM	330
1415440C Murata Power Solutions	FIXED IND 150UH 4A 69 MOHM TH	164
19R685C Murata Power Solutions	FIXED IND 6.8MH 290MA 5.7 OHM TH	0
23S3R3C Murata Power Solutions	FIXED IND 3.3UH 1.8A 31 MOHM	0
13R332C Murata Power Solutions	FIXED IND 3.3UH 4.8A 13 MOHM TH	50
491R0SC Murata Power Solutions	FIXED IND 1UH 11.8A 5 MOHM SMD	43
18R333C Murata Power Solutions	FIXED IND 33UH 2A 40 MOHM TH	65

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