Fixed Inductors

Part Number	Description / PDF	Quantity
IHLP2525CZERR68M06 Vishay / Dale	FIXED IND 680NH 15.5A 5.2 MOHM	0
SRN4018-100M J.W. Miller / Bourns	FIXED IND 10UH 1.3A 180 MOHM SMD	656
0805CS-751EKTS Delta Electronics	FIXED IND 750NH 180MA 2.3 OHM	3978
MHQ1005P1N6BT000 TDK Corporation	FIXED IND 1.6NH 1A 40 MOHM SMD	29434
LQW18AN4N9C80D TOKO / Murata	FIXED IND 4.9NH 1.2A 81 MOHM SMD	3689
S1008R-272H API Delevan	FIXED IND 2.7UH 365MA 850 MOHM	0
LMLP0707M8R2DTAS Elco (AVX)	FIXED IND 8.2UH 3.2A 116MOHM SMD	1500
LQW18AN19NJ80D TOKO / Murata	FIXED IND 19NH 1.4A 75 MOHM SMD	1095
IHSM5832ER271L Vishay / Dale	FIXED IND 270UH 640MA 1.27 OHM	0
LQW15AN2N2G8ZD TOKO / Murata	FIXED IND 2.2NH 2.53A 22 MOHM	354
NLCV32T-101K-EF TDK Corporation	FIXED IND 100UH 120MA 4.81 OHM	6030
744786210A Würth Elektronik Midcom	FIXED IND 100NH 300MA 1.2 OHM	26211
DC780-102L API Delevan	FIXED IND 1UH 11.4A 3 MOHM TH	0
HF1008R-100M API Delevan	FIXED IND 10NH 1.235A 80 MOHM	0
VLS201612HBX-R68M-1 TDK Corporation	FIXED IND 680NH 2.77A 54 MOHM	678
DFEG7030D-220M=P3 TOKO / Murata	FIXED IND 22UH 1.9A 198 MOHM	0
2100HT-1R5-H-RC J.W. Miller / Bourns	FIXED IND 1.5UH 19.8A 3 MOHM TH	0
NLFC453232T-150K-PF TDK Corporation	FIXED IND 15UH 200MA 300 MOHM	470
AISC-0603HP-56NJ-T Abracon	FIXED IND 56NH 700MA 230 MOHM	0
S1008R-333J API Delevan	FIXED IND 33UH 125MA 7.4 OHM SMD	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