Fixed Inductors

Part Number	Description / PDF	Quantity
156G Hammond Manufacturing	FIXED IND 9H 40MA 300 OHM CHASS	17
195M30 Hammond Manufacturing	FIXED IND 20MH 30A 45 MOHM CHASS	1
159ZJ Hammond Manufacturing	FIXED IND 10MH 5A 160 MOHM CHASS	0
153H Hammond Manufacturing	FIXED IND 2.2H 50MA 305 OHM CHAS	6
156B Hammond Manufacturing	FIXED IND 1.5MH 5A 70 MOHM CHASS	25
1536E Hammond Manufacturing	FIXED IND 4.9UH 15A 16 MOHM TH	88
194B Hammond Manufacturing	FIXED IND 4H 90MA 108 OHM CHASS	7
157M Hammond Manufacturing	FIXED IND 8H 100MA 259 OHM CHASS	2
195G20 Hammond Manufacturing	FIXED IND 5MH 20A 25 MOHM CHASS	1
157L Hammond Manufacturing	FIXED IND 14H 75MA 429 OHM CHASS	13
1539M32 Hammond Manufacturing	FIXED IND 10MH 1.5A 1.55 OHM TH	0
195E50 Hammond Manufacturing	FIXED IND 2.5MH 50A 8 MOHM CHASS	4
195G10 Hammond Manufacturing	FIXED IND 5MH 10A 40 MOHM CHASS	28
195J30 Hammond Manufacturing	FIXED IND 10MH 30A 37 MOHM CHASS	10
1539M15 Hammond Manufacturing	FIXED IND 250UH 4.6A 83 MOHM TH	15
1539M27 Hammond Manufacturing	FIXED IND 250UH 9A 40 MOHM TH	13
195G30 Hammond Manufacturing	FIXED IND 5MH 30A 23 MOHM CHASS	8
1539M20 Hammond Manufacturing	FIXED IND 100UH 9.8A 25 MOHM TH	32
195E100 Hammond Manufacturing	FIXED IND 2.5MH 100A 6 MOHM CHAS	1
1539M07 Hammond Manufacturing	FIXED IND 500UH 2A 378 MOHM TH	105

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