Fixed Inductors

Part Number	Description / PDF	Quantity
CDRH125NP-471MC Sumida Corporation	FIXED IND 470UH 580MA 770 MOHM	0
CDRH73NP-560MC-B Sumida Corporation	FIXED IND 56UH 680MA 470 MOHM	0
CDRH64BNP-120MC-B Sumida Corporation	FIXED IND 12UH 1.2A 130 MOHM SMD	43
CDR125NP-560MC Sumida Corporation	FIXED IND 56UH 1.38A 150 MOHM	0
CDRH125NP-330MC Sumida Corporation	FIXED IND 33UH 2.1A 57 MOHM SMD	3928
CDEIR6D31FHF-2R2MC Sumida Corporation	FIXED IND 2.2UH 6.5A 12 MOHM SMD	0
CDRH60D45BT150NP-150MC Sumida Corporation	FIXED IND 15UH 2A 76.8MOHM SMD	1980
CR54NP-560KC Sumida Corporation	FIXED IND 56UH 680MA 420 MOHM	0
CDRH3D28NP-100NC Sumida Corporation	FIXED IND 10UH 1.18A 145 MOHM	44423
CEP125NP-1R4MC-U Sumida Corporation	FIXED IND 1.4UH 15.5A 3.4 MOHM	71
CDRH127/LDNP-120MC Sumida Corporation	FIXED IND 12UH 6.45A 21.3 MOHM	2691
CDRH5D18NP-820NC Sumida Corporation	FIXED IND 82UH 410MA 978 MOHM	0
0315CDMCCDS-R82MC Sumida Corporation	FIXED IND 820NH 5A 32MOHM SMD	3000
CDEP105NP-1R3MC-50 Sumida Corporation	FIXED IND 1.3UH 11.2A 5.3 MOHM	0
CDRH2D14NP-6R8NC Sumida Corporation	FIXED IND 6.8UH 920MA 213 MOHM	0
CDRH62BNP-180MC-B Sumida Corporation	FIXED IND 18UH 800MA 270 MOHM	0
CDR125NP-330MC Sumida Corporation	FIXED IND 33UH 1.8A 100 MOHM SMD	0
CDRH2D11/HPNP-3R3NC Sumida Corporation	FIXED IND 3.3UH 900MA 173 MOHM	0
CR32NP-121KC Sumida Corporation	FIXED IND 120UH 185MA 2.9 OHM	0
RCH106NP-102K Sumida Corporation	FIXED IND 1MH 360MA 3.2 OHM TH	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