Fixed Inductors

Part Number	Description / PDF	Quantity
CD75NP-820KC Sumida Corporation	FIXED IND 82UH 780MA 370 MOHM	0
CDRH125NP-120MC Sumida Corporation	FIXED IND 12UH 3.5A 27 MOHM SMD	0
CDRH5D28NP-470NC Sumida Corporation	FIXED IND 47UH 620MA 250 MOHM	2658
CDRH127/LDNP-5R8NC Sumida Corporation	FIXED IND 5.8UH 8.6A 16.2 MOHM	0
0512CDMCCDS-R56MC Sumida Corporation	FIXED IND 560NH 7.2A 18.6MOHM SM	4000
CD54NP-220MC Sumida Corporation	FIXED IND 22UH 1.11A 180 MOHM	6090
CDR7D43MNNP-4R7NC Sumida Corporation	FIXED IND 4.7UH 4A 21.4 MOHM SMD	0
CDR63BNP-150MC Sumida Corporation	FIXED IND 15UH 860MA 180 MOHM	0
CD75NP-150KC Sumida Corporation	FIXED IND 15UH 1.8A 90 MOHM SMD	1002
CD43NP-2R7MC Sumida Corporation	FIXED IND 2.7UH 2.16A 78.7 MOHM	0
CR32NP-331KC Sumida Corporation	FIXED IND 330UH 125MA 7 OHM SMD	0
CDRH5D28RNP-6R0NC Sumida Corporation	FIXED IND 6UH 1.7A 41.9 MOHM SMD	0
CDRH60D45BT150NP-2R2NC Sumida Corporation	FIXED IND 2.2UH 4.1A 19.5 MOHM	2000
CDRH6D12NP-2R2NC Sumida Corporation	FIXED IND 2.2UH 2.3A 50 MOHM SMD	1091
CDRH127NP-3R5NC Sumida Corporation	FIXED IND 3.5UH 7.5A 13.5 MOHM	6172
125CDMCCDS-4R7MC Sumida Corporation	FIXED IND 4.7UH 14A 10MOHM SMD	10001
CDRH6D28NP-3R0NC Sumida Corporation	FIXED IND 3UH 3A 24 MOHM SMD	9008
CD75NP-680KC Sumida Corporation	FIXED IND 68UH 850MA 280 MOHM	0
CD73NP-331KC Sumida Corporation	FIXED IND 330UH 280MA 1.495 OHM	0
CDRH5D16NP-220MC Sumida Corporation	FIXED IND 22UH 800MA 320 MOHM	4366

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