Fixed Inductors

Part Number	Description / PDF	Quantity
1538M21 Hammond Manufacturing	FIXED IND 5UH 23A 4 MOHM TH	20
1539M02 Hammond Manufacturing	FIXED IND 10UH 14A 8 MOHM TH	0
156C Hammond Manufacturing	FIXED IND 150H 8MA 3.7 KOHM CHAS	22
158T Hammond Manufacturing	FIXED IND 1H 300MA 40 OHM CHASS	5
155H Hammond Manufacturing	FIXED IND 5H 50MA 270 OHM CHASS	32
195C100 Hammond Manufacturing	FIXED IND 1MH 100A 3.6 MOHM CHAS	18
158S Hammond Manufacturing	FIXED IND 1.5H 250MA 60 OHM CHAS	21
1540M22 Hammond Manufacturing	FIXED IND 900UH 3.75A 175 MOHM	15
156L Hammond Manufacturing	FIXED IND 5H 75MA 135 OHM CHASS	28
193V Hammond Manufacturing	FIXED IND 150MH 3A 1 OHM CHASSIS	22
195C50 Hammond Manufacturing	FIXED IND 1MH 50A 5 MOHM CHASSIS	16
194F Hammond Manufacturing	FIXED INDUCTOR 5H 120MA CHASSIS	6
193CP Hammond Manufacturing	FIXED IND 20H 100MA 184 OHM CHAS	1
195M20 Hammond Manufacturing	FIXED IND 20MH 20A 75 MOHM CHASS	2
195J20 Hammond Manufacturing	FIXED IND 10MH 20A 45 MOHM CHASS	36
1539M12 Hammond Manufacturing	FIXED IND 25UH 14A 9 MOHM TH	30
PWDI13158 Hammond Manufacturing	FIXED IND	1
193JP Hammond Manufacturing	FIXED IND 10H 200MA 79 OHM CHASS	2
PWDI13161 Hammond Manufacturing	FIXED IND	0
1534C Hammond Manufacturing	FIXED IND 2.4MH 160MA 15 OHM TH	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