Fixed Inductors

Part Number	Description / PDF	Quantity
LQP15MN1N7W02D TOKO / Murata	FIXED IND 1.7NH 280MA 200 MOHM	5992
LQG15WZ2N8S02D TOKO / Murata	FIXED IND 2.8NH 900MA 80 MOHM	7715
LQP02HQ2N1C02E TOKO / Murata	FIXED IND 2.1NH 650MA 100 MOHM	0
LQH66SN1R5M03L TOKO / Murata	FIXED IND 1.5UH 3.8A 22.4 MOHM	324
1217AS-H-4R7N=P3 TOKO / Murata	FIXED IND 4.7UH 6.3A 18 MOHM SMD	750
LQP02HQ16NJ02L TOKO / Murata	FIXED IND 16NH 170MA 1.53 OHM	0
LQP02HQ20NJ02L TOKO / Murata	FIXED IND 20NH 140MA 2.26 OHM	0
LQW15AW68NJ80D TOKO / Murata	FIXED IND 68NH 480MA 560 MOHM	10000
LQM18PN1R0NF0L TOKO / Murata	FIXED IND 1UH 600MA 350 MOHM SMD	273
MDH12577C-6R8NA=P3 TOKO / Murata	FIXED IND 6.8UH 4.8A 12MOHM SMD	0
LQW2UAS27NG00L TOKO / Murata	FIXED IND 27NH 1A 130 MOHM SMD	0
LQH43MN1R0M03L TOKO / Murata	FIXED IND 1UH 500MA 200 MOHM SMD	3917
LQP03TG3N7C02D TOKO / Murata	FIXED IND 3.7NH 350MA 350 MOHM	1249
LQH32NH470J23L TOKO / Murata	FIXED IND 47UH 155MA 1.752 OHM	3099
DFE252012P-4R7M=P2 TOKO / Murata	FIXED IND 4.7UH 2A 200 MOHM SMD	3063
LQP03TN4N0C02D TOKO / Murata	FIXED IND 4NH 350MA 400 MOHM SMD	0
1217AS-H-100M=P3 TOKO / Murata	FIXED IND 10UH 3.9A 39.6 MOHM	2773
LQW18AN94NG8ZD TOKO / Murata	FIXED IND 94NH 490MA 630 MOHM	7381
LQH31MN560J03L TOKO / Murata	FIXED IND 56UH 50MA 8.9 OHM SMD	0
LQG15HH5N6C02D TOKO / Murata	FIXED IND 5.6NH 650MA 180 MOHM	7495

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