Fixed Inductors

Part Number	Description / PDF	Quantity
L-14W18NKV4E Johanson Technology	FIXED IND 18NH 700MA 170 MOHM	0
L-05B6N8JV6T Johanson Technology	FIXED IND 6.8NH 250MA 700 MOHM	14390
L-07W5N6CV4T Johanson Technology	FIXED IND 5.6NH 760MA 83 MOHM	0
L-07C27NJV6T Johanson Technology	FIXED IND 27NH 200MA 900 MOHM	1123
L-07C23NJV6T Johanson Technology	FIXED IND 23NH 200MA 850 MOHM	0
L-07W12NKV4T Johanson Technology	FIXED IND 12NH 640MA 120 MOHM	0
L-15F5R6KV4E Johanson Technology	FIXED IND 5.6UH 160MA 3 OHM SMD	0
L-15F1R0KV4E Johanson Technology	FIXED IND 1UH 180MA 2.13 OHM SMD	0
L-15W2N2SV4E Johanson Technology	FIXED IND 2.2NH 800MA 60 MOHM	0
L-07C5N1SV6T Johanson Technology	FIXED IND 5.1NH 300MA 260 MOHM	120596
L-14CR22KV4T Johanson Technology	FIXED IND 220NH 300MA 2.8 OHM	0
L-14CR18JV4T Johanson Technology	FIXED IND 180NH 300MA 2.7 OHM	30518
L-15WR27GV4E Johanson Technology	FIXED IND 270NH 350MA 1.46 OHM	0
L-14C15NJV4T Johanson Technology	FIXED IND 15NH 300MA 550 MOHM	1331
L-14W82NJV4E Johanson Technology	FIXED IND 82NH 400MA 540 MOHM	0
L-14W10NKV4E Johanson Technology	FIXED IND 10NH 700MA 130 MOHM	0
L-15W33NGV4E Johanson Technology	FIXED IND 33NH 500MA 150 MOHM	0
L-14W56NGV4E Johanson Technology	FIXED IND 56NH 600MA 310 MOHM	0
L-07C6N8JV6T Johanson Technology	FIXED IND 6.8NH 250MA 320 MOHM	47461
L-15F3R9JV4E Johanson Technology	FIXED IND 3.9UH 200MA 2.5 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