Fixed Inductors

Part Number	Description / PDF	Quantity
CDRH73NP-681MC-B Sumida Corporation	FIXED IND 680UH 190MA 5.73 OHM	0
SH150S-1.26-112 Amgis	FIXED IND 112UH 1.26A 300 MOHM	2562
CLF12577NIT-3R3N-D TDK Corporation	FIXED IND 3.3UH 9.5A 10.01 MOHM	92
MAMK2520T1R0M TAIYO YUDEN	FIXED IND 1UH 2.7A 59 MOHM SMD	278583
CIH10T12NJNC Samsung Electro-Mechanics	FIXED IND 12NH 600MA 280 MOHM	3833
5500R-334K API Delevan	FIXED IND 330UH 1.97A 257 MOHM	0
NRM6045T330MMRRV TAIYO YUDEN	FIXED INUCTOR 33UH 216 MOHM SMD	0
LQW2BAS1R0J00L TOKO / Murata	FIXED IND 1UH 170MA 2.4 OHM SMD	1845
PA4990.101HLT PulseLarsen Antenna	FIXED IND 100NH 77A 0.125 MOHM	33453780
B82422A3221J100 TDK EPCOS	FIXED IND 220NH 280MA 640 MOHM	0
SRP0415-1R0K J.W. Miller / Bourns	FIXED IND 1UH 6.1A 22.5 MOHM SMD	3586
IMC1812BN82NM Vishay / Dale	FIXED IND 82NH 450MA 400 MOHM	0
7447713033 Würth Elektronik Midcom	FIXED IND 3.3UH 4.6A 24 MOHM SMD	70
LMLP0707NR10DTAS Elco (AVX)	FIXED INDUCTOR 100NH SMD	1500
IMC1812BN120K Vishay / Dale	FIXED IND 12UH 225MA 2 OHM SMD	0
55082703400 Sumida Corporation	FIXED IND 27NH 600MA 90 MOHM SMD	0
AISC-1008F-1R5G-T Abracon	FIXED IND 1.5UH 630MA 760 MOHM	1400
LQW18AN75NG8ZD TOKO / Murata	FIXED IND 75NH 590MA 410 MOHM	5410
CLF10040T-151M-CA TDK Corporation	FIXED IND 150UH 800MA 456 MOHM	587
LQG15HZ68NH02D TOKO / Murata	FIXED IND 68NH 250MA 920 MOHM	1797

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