Fixed Inductors

Part Number	Description / PDF	Quantity
1538M16 Hammond Manufacturing	FIXED IND 10UH 16A 8 MOHM TH	25
195M10 Hammond Manufacturing	FIXED IND 20MH 10A 13 MOHM CHASS	18
1538M02 Hammond Manufacturing	FIXED IND 10UH 9A 17 MOHM TH	151
1537R Hammond Manufacturing	FIXED IND 1MH 1.25A 830 MOHM TH	11
154H Hammond Manufacturing	FIXED IND 4H 50MA 300 OHM CHASS	20
1538M15 Hammond Manufacturing	FIXED IND 5UH 19A 6 MOHM TH	0
193MP Hammond Manufacturing	FIXED IND 10H 300MA 63 OHM CHASS	2
195P5 Hammond Manufacturing	FIXED IND 30MH 5A 230 MOHM CHASS	47
194C Hammond Manufacturing	FIXED IND 40H 50MA 420.2 OHM	11
195T10 Hammond Manufacturing	FIXED IND 100MH 10A 420 MOHM	7
1536P Hammond Manufacturing	FIXED IND 40UH 3A 82 MOHM TH	86
1539M19 Hammond Manufacturing	FIXED IND 50UH 14A 12 MOHM TH	31
156M Hammond Manufacturing	FIXED IND 3H 100MA 86 OHM CHASS	14
1538M14 Hammond Manufacturing	FIXED IND 150UH 6.3A 46 MOHM TH	10
1540M23 Hammond Manufacturing	FIXED IND 1.8MH 2.5A 550 MOHM TH	15
1532D Hammond Manufacturing	FIXED IND 39UH 600MA 650 MOHM TH	80
157H Hammond Manufacturing	FIXED IND 10H 50MA 408 OHM CHASS	15
1540M17 Hammond Manufacturing	FIXED IND 500UH 4A 150 MOHM TH	20
158L Hammond Manufacturing	FIXED IND 15H 75MA 411 OHM CHASS	5
155B Hammond Manufacturing	FIXED IND 6MH 2A 300 MOHM CHASS	203

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