Fixed Inductors

Part Number	Description / PDF	Quantity
1539M24 Hammond Manufacturing	FIXED IND 2.5MH 2.2A 499 MOHM TH	0
1537P Hammond Manufacturing	FIXED IND 750UH 2A 465 MOHM TH	32
1539M26 Hammond Manufacturing	FIXED IND 100UH 14A 18 MOHM TH	0
154E Hammond Manufacturing	FIXED IND 20H 20MA 1.666K OHM	11
1540M05 Hammond Manufacturing	FIXED IND 450UH 1.5A 490 MOHM TH	0
159Q Hammond Manufacturing	FIXED IND 7H 150MA 100 OHM CHASS	3
1538M22 Hammond Manufacturing	FIXED IND 10UH 20A 6 MOHM TH	112
193K Hammond Manufacturing	FIXED IND 2.6H 300MA 21 OHM CHAS	2
193G Hammond Manufacturing	FIXED IND 10H 150MA 102 OHM CHAS	3
1532B Hammond Manufacturing	FIXED IND 15UH 1A 170 MOHM TH	313
1538M20 Hammond Manufacturing	FIXED IND 100UH 10A 27 MOHM TH	73
193GP Hammond Manufacturing	FIXED IND 10H 150MA 103 OHM CHAS	2
157G Hammond Manufacturing	FIXED IND 30H 40MA 595 OHM CHASS	4
1536F Hammond Manufacturing	FIXED IND 8.8UH 10A 21 MOHM TH	40
155J Hammond Manufacturing	FIXED IND 15H 30MA 1.026K OHM	17
159ZL Hammond Manufacturing	FIXED IND 2.5MH 10A 44 MOHM CHAS	15
1539M13 Hammond Manufacturing	FIXED IND 50UH 10A 17 MOHM TH	11
195R10 Hammond Manufacturing	FIXED IND 50MH 10A 165 MOHM CHAS	3
1538M08 Hammond Manufacturing	FIXED IND 5UH 14A 9 MOHM TH	66
1539M06 Hammond Manufacturing	FIXED IND 250UH 2.9A 173 MOHM TH	7

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