Fixed Inductors

Part Number	Description / PDF	Quantity
CDRH6D28NP-560NC Sumida Corporation	FIXED IND 56UH 730MA 277 MOHM	0
CDRH127/LDNP-221MC Sumida Corporation	FIXED IND 220UH 1.45A 338 MOHM	7675
0420CDMCCDS-6R8MC Sumida Corporation	FIXED IND 6.8UH 2.1A 175 MOHM	5637
CDRH8D38/ANP-470MC Sumida Corporation	FIXED IND 47UH 780MA 225 MOHM	0
CD43NP-390KC Sumida Corporation	FIXED IND 39UH 520MA 587 MOHM	0
CDRH60D45BT150NP-1R0NC Sumida Corporation	FIXED IND 1UH 4.8A 14.3 MOHM SMD	1983
CD30D22HF-220MC Sumida Corporation	FIXED IND 22UH 660MA 643 MOHM	0
CDEP147NP-0R4NC-95 Sumida Corporation	FIXED IND 400NH 23A 1.18 MOHM	0
RCP1317NP-471L Sumida Corporation	FIXED IND 470UH 1.15A 530 MOHM	0
54065603400 Sumida Corporation	FIXED IND 56NH 310MA 290 MOHM	0
CDEP147NP-3R1MC-125 Sumida Corporation	FIXED IND 3.1UH 17.5A 3.23 MOHM	834
CDR7D28MNNP-221NC Sumida Corporation	FIXED IND 220UH 400MA 1.32 OHM	820
CDPH4D19FNP-470MC Sumida Corporation	FIXED IND 47UH 1.03A 293 MOHM	4075
CDR7D28MNNP-100NC Sumida Corporation	FIXED IND 10UH 2.5A 53.8 MOHM	6647
CDRH5D28RNP-680NC Sumida Corporation	FIXED IND 68UH 480MA 351 MOHM	0
104CDMCCDS-220MC Sumida Corporation	FIXED IND 22UH 5A 66 MOHM SMD	8093
CDRH125NP-560MC Sumida Corporation	FIXED IND 56UH 1.7A 110 MOHM SMD	433
CDRH70D45BT150NP-680MC Sumida Corporation	FIXED IND 68UH 1.57A 190MOHM SMD	1967
CD43NP-560KC Sumida Corporation	FIXED IND 56UH 420MA 937 MOHM	0
CDRH105RNP-221NC Sumida Corporation	FIXED IND 220UH 940MA 500 MOHM	511

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