Fixed Inductors

Image	Part Number	Description / PDF	Quantity	Rfq
	L-14W40NKV4E Johanson Technology	FIXED IND 40NH 600MA SMD	0
	L-14C36NJV4T Johanson Technology	FIXED IND 36NH 300MA SMD	0
	L-14W30NKV4E Johanson Technology	FIXED IND 30NH 600MA 220 MOHM	0
	L-15W2N4SV4E Johanson Technology	FIXED IND 2.4NH 800MA SMD	0
	L-07W3N6SV4T Johanson Technology	FIXED IND 3.6NH 840MA 66 MOHM	0
	L-07C40NJV4T Johanson Technology	FIXED IND 40NH SMD	0
	L-14W13NJV4E Johanson Technology	FIXED IND 13NH 700MA SMD	0
	L-07C30NKV4T Johanson Technology	FIXED IND 30NH 200MA SMD	0
	L-14W2N2SV4E Johanson Technology	FIXED IND 2.2NH 700MA 80 MOHM	0
	L-07CR12KV4T Johanson Technology	FIXED IND 120NH 100MA 2.5 OHM	0
	L-07CR10KV4T Johanson Technology	FIXED IND 100NH 100MA 2.5 OHM	0
	L-14C40NKV4T Johanson Technology	FIXED IND 40NH 300MA SMD	0
	L-14W23NGV4E Johanson Technology	FIXED IND 23NH 700MA 220 MOHM	0
	L-15W36NKV4E Johanson Technology	FIXED IND 36NH 500MA SMD	0
	L-14W5N1SV4E Johanson Technology	FIXED IND 5.1NH 700MA 110 MOHM	0
	L-07C2N0SV4T Johanson Technology	FIXED IND 2NH 300MA 160 MOHM SMD	0
	L-07C1N0SV4T Johanson Technology	FIXED IND 1NH 300MA 120 MOHM SMD	0
	L-07C24NJV4T Johanson Technology	FIXED IND 24NH 200MA SMD	0
	L-07C82NKV4T Johanson Technology	FIXED IND 82NH 100MA 2.5 OHM SMD	0
	L-03C3N9SV4T Johanson Technology	FIXED IND 3.9NH 200MA 600 MOHM	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