Fixed Inductors

Part Number	Description / PDF	Quantity
LMCI0201-3N7ST Venkel LTD	FIXED IND 3.7NH 230MA 400 MOHM	0
LMCI0201-6N8JT Venkel LTD	FIXED IND 6.8NH 200MA 500 MOHM	15000
LMCI0201-22NJT Venkel LTD	FIXED IND 22NH 130MA 1.2OHM SMD	0
LMCI0201-2N3ST Venkel LTD	FIXED IND 2.3NH 330MA 200 MOHM	0
LMCI0201-2N4ST Venkel LTD	FIXED IND 2.4NH 310MA 220 MOHM	0
LMCI0201-12NJT Venkel LTD	FIXED IND 12NH 160MA 800MOHM SMD	15000
LMCI0201-3N5ST Venkel LTD	FIXED IND 3.5NH 250MA 340 MOHM	0
LMCI0201-33NJT Venkel LTD	FIXED IND 33NH 110MA 2.2OHM SMD	0
LMCI0201-2N7ST Venkel LTD	FIXED IND 2.7NH 310MA 220 MOHM	15000
LMCI0201-10NJT Venkel LTD	FIXED IND 10NH 160MA 800MOHM SMD	15000
LMCI0201-1N4ST Venkel LTD	FIXED IND 1.4NH 440MA 110 MOHM	0
LMCI0201-4N7ST Venkel LTD	FIXED IND 4.7NH 220MA 450 MOHM	30000
LMCI0201-18NJT Venkel LTD	FIXED IND 18NH 140MA 1OHM SMD	0
LMCI0201-0N8ST Venkel LTD	FIXED IND 0.8NH 550MA 70MOHM SMD	0
LMCI0201-2N1ST Venkel LTD	FIXED IND 2.1NH 300MA 240 MOHM	0
LMCI0201-3N3ST Venkel LTD	FIXED IND 3.3NH 270MA 300 MOHM	15000
LMCI0201-1N2ST Venkel LTD	FIXED IND 1.2NH 420MA 120 MOHM	15000
LMCI0201-15NJT Venkel LTD	FIXED IND 15NH 160MA 850MOHM SMD	15000
TFI0402Q-3N9BT Venkel LTD	FIXED IND 3.9NH 460MA 350 MOHM	0
LMCI0201-1N9ST Venkel LTD	FIXED IND 1.9NH 350MA 180 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