Fixed Inductors

Part Number	Description / PDF	Quantity
7447773062 Würth Elektronik Midcom	FIXED IND 6.2UH 3.2A 30 MOHM SMD	0
744373770056 Würth Elektronik Midcom	FIXED IND 560NH 18.5A 1.7 MOHM	0
74439370068 Würth Elektronik Midcom	FIXED IND 6.8UH 15A 4.1 MOHM	299
744040240047 Würth Elektronik Midcom	FIXED IND 470NH 2.6A 32 MOHM SMD	0
74404063047 Würth Elektronik Midcom	FIXED IND 4.7UH 3.08A 30 MOHM	2457
7440329002 Würth Elektronik Midcom	FIXED IND 2.2UH 790MA 126 MOHM	1713
7447860110 Würth Elektronik Midcom	FIXED IND 10NH 300MA 260 MOHM	12000
7447840118 Würth Elektronik Midcom	FIXED IND 18NH 300MA 510 MOHM	9767
744770015 Würth Elektronik Midcom	FIXED IND 1.5UH 10A 6 MOHM SMD	0
7443739650068 Würth Elektronik Midcom	FIXED IND 680NH 24A 1.5 MOHM SMD	966
744028001 Würth Elektronik Midcom	FIXED IND 1UH 1.75A 85 MOHM SMD	6000
744784222A Würth Elektronik Midcom	FIXED IND 220NH 100MA 4 OHM SMD	1000
744383430056 Würth Elektronik Midcom	FIXED IND 560NH 2.1A 73 MOHM SMD	0
7440660015 Würth Elektronik Midcom	FIXED IND 1.5UH 7.2A 7.5 MOHM	599
7447820082 Würth Elektronik Midcom	FIXED IND 8.2NH 230MA 450 MOHM	15000
750312186 Würth Elektronik Midcom	FIXED IND 696UH 2A 128 MOHM TH	49
744916130 Würth Elektronik Midcom	FIXED IND 30NH 450MA 400 MOHM	0
7447783330 Würth Elektronik Midcom	FIXED IND 33UH 1.32A 165 MOHM	0
7447820012 Würth Elektronik Midcom	FIXED IND 1.2NH 450MA 120 MOHM	14960
744771182 Würth Elektronik Midcom	FIXED IND 82UH 1.65A 140 MOHM	99

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