Fixed Inductors

Part Number	Description / PDF	Quantity
CDRH4D28NP-270NC Sumida Corporation	FIXED IND 27UH 580MA 261 MOHM	0
RCP1317NP-271L Sumida Corporation	FIXED IND 270UH 1.55A 330 MOHM	0
CDRH127/LDNP-681MC Sumida Corporation	FIXED IND 680UH 850MA 1.13 OHM	0
CDPH28D11FHF-1R0NC Sumida Corporation	FIXED IND 1UH 1.83A 62 MOHM SMD	0
CDRH127/LDNP-270MC Sumida Corporation	FIXED IND 27UH 4.2A 41.6 MOHM	1153
CDRH103RNP-100NC-B Sumida Corporation	FIXED IND 10UH 2.8A 59 MOHM SMD	2314
CDRH5D28NP-2R5NC Sumida Corporation	FIXED IND 2.5UH 2.6A 18 MOHM SMD	13902
CDRH73NP-471MC-B Sumida Corporation	FIXED IND 470UH 240MA 4.18 OHM	0
CDRH8D58/LDNP-220NC Sumida Corporation	FIXED IND 22UH 3.3A 45.3 MOHM	0
CDRH6D38NP-101NC Sumida Corporation	FIXED IND 100UH 650MA 358 MOHM	0
CDMT40D20HF-2R2NC Sumida Corporation	FIXED IND 2.2UH 3.5A 30.8 MOHM	107
CD104NP-181KC Sumida Corporation	FIXED IND 180UH 560MA 621 MOHM	0
CD104NP-150MC Sumida Corporation	FIXED IND 15UH 1.87A 70 MOHM SMD	0
CEP125NP-0R8MC Sumida Corporation	FIXED IND 800NH 16.5A 2.5 MOHM	0
CDRH2D14NP-R60NC Sumida Corporation	FIXED IND 600NH 3.45A 33 MOHM	0
CDRH5D18NP-560NC Sumida Corporation	FIXED IND 56UH 500MA 665 MOHM	0
CDPH4D19FNP-330MC Sumida Corporation	FIXED IND 33UH 1.25A 200 MOHM	1724
CD73NP-390MC Sumida Corporation	FIXED IND 39UH 740MA 217 MOHM	0
CDRH124NP-680MC Sumida Corporation	FIXED IND 68UH 1.5A 220 MOHM SMD	1990
0512CDMCCDS-1R0MC Sumida Corporation	FIXED IND 1UH 5.7A 31.8MOHM SMD	3370

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