Fixed Inductors

Part Number	Description / PDF	Quantity
CDEP149NP-1R8MC-H Sumida Corporation	FIXED IND 1.8UH 28A 2.3 MOHM SMD	0
CDRH4D18NP-4R7NC Sumida Corporation	FIXED IND 4.7UH 840MA 162 MOHM	1
CD43NP-2R2MC Sumida Corporation	FIXED IND 2.2UH 2.25A 71.2 MOHM	0
CDRH124NP-390MC Sumida Corporation	FIXED IND 39UH 2.1A 132 MOHM SMD	0
CDRH70D45BT150NP-150MC Sumida Corporation	FIXED IND 15UH 3.1A 55MOHM SMD	2000
CDRH70D45BT150NP-6R8NC Sumida Corporation	FIXED IND 6.8UH 5.1A 22MOHM SMD	1955
CDRH4D28CNP-100PC Sumida Corporation	FIXED IND 10UH 1.26A 106 MOHM	9945
CD104NP-100MC Sumida Corporation	FIXED IND 10UH 2.38A 53 MOHM SMD	445
CDRH125NP-220MC Sumida Corporation	FIXED IND 22UH 2.8A 36 MOHM SMD	100
CDR63BNP-470LC Sumida Corporation	FIXED IND 47UH 500MA 510 MOHM	0
CDRH4D28CLDNP-680PC Sumida Corporation	FIXED IND 68UH 720MA 366 MOHM	0
CDPH4D19FNP-3R3MC Sumida Corporation	FIXED IND 3.3UH 3.8A 33 MOHM SMD	1956
55081503400 Sumida Corporation	FIXED IND 15NH 670MA 70 MOHM SMD	0
0420CDMCCDS-1R2MC Sumida Corporation	FIXED IND 1.2UH 6.5A 27 MOHM	2782
CDRH70D45BT150NP-1R5NC Sumida Corporation	FIXED IND 1.5UH 8.4A 9MOHM SMD	1996
CDR6D28MNNP-4R5NC Sumida Corporation	FIXED IND 4.5UH 2.4A 57.5 MOHM	0
CDR6D23MNNP-6R1NC Sumida Corporation	FIXED IND 6.1UH 1.8A 66.3 MOHM	0
CDRH104RNP-470NC Sumida Corporation	FIXED IND 47UH 1.9A 128 MOHM SMD	8723
CDRH125/LDNP-270MC Sumida Corporation	FIXED IND 27UH 3A 52 MOHM SMD	0
CDEP134NP-1R2MC-H Sumida Corporation	FIXED IND 1.2UH 15A 3.7 MOHM SMD	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