Fixed Inductors

Part Number	Description / PDF	Quantity
5598 681 34 00 Sumida Corporation	FIXED IND 680NH 95MA 3.7 OHM SMD	0
CDRH3D28NP-330NC Sumida Corporation	FIXED IND 33UH 630MA 481 MOHM	1079
252012CDMCDDS-1R0MC Sumida Corporation	FIXED IND 1UH 4.2A 42 MOHM SMD	8866
CDRH12D58/ANP-150MC Sumida Corporation	FIXED IND 15UH 3.1A 29 MOHM SMD	0
CDRH103RNP-330NC-B Sumida Corporation	FIXED IND 33UH 1.35A 202 MOHM	0
RCH110NP-681K Sumida Corporation	FIXED IND 680UH 650MA 1.1 OHM TH	3254
CEP125NP-0R8NC-U Sumida Corporation	FIXED IND 800NH 16.5A 2.5 MOHM	0
CDRH60D45BT150NP-100MC Sumida Corporation	FIXED IND 10UH 2.6A 45.6 MOHM	1987
CR32NP-101KC Sumida Corporation	FIXED IND 100UH 220MA 2.2 OHM	0
CDRH3D18NP-470NC Sumida Corporation	FIXED IND 47UH 350MA 964 MOHM	985
CDR6D28MNNP-121NC Sumida Corporation	FIXED IND 120UH 460MA 1.028 OHM	0
CDRH8D28NP-220NC Sumida Corporation	FIXED IND 22UH 1.85A 99 MOHM SMD	838
CEP123NP-6R3MC Sumida Corporation	FIXED IND 6.3UH 4.6A 20.26 MOHM	0
RCR875DNP-151K Sumida Corporation	FIXED IND 150UH 600MA 510 MOHM	0
CDRH5D16NP-680MC Sumida Corporation	FIXED IND 68UH 500MA 860 MOHM	0
CDRH2D18/LDNP-220NC Sumida Corporation	FIXED IND 22UH 680MA 320 MOHM	2041
CDRH5D16NP-150MC Sumida Corporation	FIXED IND 15UH 1.1A 200 MOHM SMD	0
55083913400 Sumida Corporation	FIXED IND 390NH 130MA 1.9 OHM	0
CDRH5D14NP-R60NC Sumida Corporation	FIXED IND 600NH 3.9A 22.7 MOHM	0
CD43NP-4R7MC Sumida Corporation	FIXED IND 4.7UH 1.62A 108.7 MOHM	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