Fixed Inductors

Part Number	Description / PDF	Quantity
S1210R-391K API Delevan	FIXED IND 390NH 692MA 400 MOHM	13661
74404042022 Würth Elektronik Midcom	FIXED IND 2.2UH 2.2A 42 MOHM SMD	1814
LQP03TN1N1B02D TOKO / Murata	FIXED IND 1.1NH 750MA 100 MOHM	58150
LQW15AN36NG8ZD TOKO / Murata	FIXED IND 36NH 540MA 431 MOHM	5798
LQP03TQ0N8W02D TOKO / Murata	FIXED IND 0.8NH 1A 50 MOHM SMD	5413
ISC1812RV2R2J Vishay / Dale	FIXED IND 2.2UH 390MA 460 MOHM	0
MGV2520104R7M-10 Laird - Performance Materials	FIXED IND 4.7UH 1.36A 262MOHM SM	4073
CDRH8D43NP-101NC Sumida Corporation	FIXED IND 100UH 800MA 360 MOHM	1638
LQW18AN78NJ8ZD TOKO / Murata	FIXED IND 78NH 590MA 410 MOHM	7294
MLF1005L1R2KT000 TDK Corporation	FIXED IND 1.2UH 35MA 790 MOHM	20709
HMLE32251B-2R2MS Delta Electronics	FIXED IND 2.2UH 2.5A 90MOHM SMD	1451
AIUR-04-101J Abracon	FIXED IND 100UH 200MA 2 OHM TH	0
B82432T1332K000 TDK EPCOS	FIXED IND 3.3UH 900MA 190 MOHM	2682
NL453232T-180J-PF TDK Corporation	FIXED IND 18UH 190MA 2.8 OHM SMD	1242
MLP2016H3R3MT0S1 TDK Corporation	FIXED IND 3.3UH 1.2A 150 MOHM	6018
IHD3EB561L Vishay / Dale	FIXED IND 560UH 1A 504 MOHM TH	0
1110-1R5M-RC J.W. Miller / Bourns	FIXED IND 1.5UH 9A 4 MOHM TH	0
DRA73-6R8-R PowerStor (Eaton)	FIXED IND 6.8UH 2.62A 41 MOHM	342
FP1208R1-R23-R PowerStor (Eaton)	FIXED IND 230NH 50A 0.29 MOHM	489
SRP1265A-R36M J.W. Miller / Bourns	FIXED IND 360NH 45A 0.9 MOHM SMD	57

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