Fixed Inductors

Part Number	Description / PDF	Quantity
CDRH2D18/HPNP-100NC Sumida Corporation	FIXED IND 10UH 900MA 245 MOHM	239
CDRH74NP-470MC-B Sumida Corporation	FIXED IND 47UH 880MA 260 MOHM	611
CD104NP-180MC Sumida Corporation	FIXED IND 18UH 1.73A 81 MOHM SMD	0
CR43NP-330KC Sumida Corporation	FIXED IND 33UH 560MA 540 MOHM	177
CDRH124NP-560MC Sumida Corporation	FIXED IND 56UH 1.8A 190 MOHM SMD	0
CDR6D28MNNP-330NC Sumida Corporation	FIXED IND 33UH 940MA 308.8 MOHM	0
CDR105NP-180MC Sumida Corporation	FIXED IND 18UH 1.89A 80 MOHM SMD	0
RCH106NP-470K Sumida Corporation	FIXED IND 47UH 1.7A 160 MOHM TH	0
CEP125NP-0R4NC-HD Sumida Corporation	FIXED IND 470NH 28.8A 1.5 MOHM	0
CDR6D28MNNP-560NC Sumida Corporation	FIXED IND 56UH 680MA 501.3 MOHM	0
125CDMCCDS-220MC Sumida Corporation	FIXED IND 22UH 6.5A 40.4MOHM SMD	31
CDRH5D18NP-5R4NC Sumida Corporation	FIXED IND 5.4UH 1.6A 76 MOHM SMD	3061
CDRH8D38NP-220NC Sumida Corporation	FIXED IND 22UH 2A 105 MOHM SMD	290
CDRH6D28NP-5R0NC Sumida Corporation	FIXED IND 5UH 2.4A 31 MOHM SMD	23985
CDRH125L125NP-681MC Sumida Corporation	FIXED IND 680UH 650MA 1.22 OHM	495
CDRH8D28NP-101NC Sumida Corporation	FIXED IND 100UH 800MA 430 MOHM	0
CDRH125NP-150MC Sumida Corporation	FIXED IND 15UH 3.3A 30 MOHM SMD	5812
CDRH127NP-560MC Sumida Corporation	FIXED IND 56UH 2.35A 110 MOHM	422
CDRH5D14NP-3R3NC Sumida Corporation	FIXED IND 3.3UH 2.4A 53.7 MOHM	0
CDPH4D19FNP-6R8MC Sumida Corporation	FIXED IND 6.8UH 3.02A 50 MOHM	1706

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