Fixed Inductors

Part Number	Description / PDF	Quantity
SCIHP0718-1R0M Signal Transformer	FIXED IND 1UH 7A 18.5 MOHM SMD	827
HCTI-180-4.8 Signal Transformer	FIXED IND 180UH 4.8A 78 MOHM TH	0
SCIH1040HC-R68M Signal Transformer	FIXED IND 680NH 22A 2.4 MOHM SMD	0
HCTI-220-5.8 Signal Transformer	FIXED IND 220UH 5.8A 54 MOHM TH	742
SCRH8D43-680 Signal Transformer	FIXED IND 68UH 1.2A 240 MOHM SMD	1067
SCEP147H-R30 Signal Transformer	FIXED IND 300NH 23A 2.1 MOHM SMD	0
SCEP147L-120 Signal Transformer	FIXED IND 12UH 9A 13.3 MOHM SMD	0
HCTI-820-2.6 Signal Transformer	FIXED IND 820UH 2.6A 270 MOHM TH	10
SCIHP0420TB-1R2 Signal Transformer	FIXED INDUCTOR 1.2UH 4.5A SMD	0
SCEP134H-R30 Signal Transformer	FIXED IND 300NH 18A 2.5 MOHM SMD	0
SCIHP0412-R047 Signal Transformer	FIXED INDUCTOR 47NH 13A SMD	5311
HCTI-330-5.2 Signal Transformer	FIXED IND 330UH 5.2A 67 MOHM TH	391
SCRH73B-331 Signal Transformer	FIXED IND 330UH 280MA 2.62 OHM	0
SCRH127-471 Signal Transformer	FIXED IND 470UH 920MA 980 MOHM	495
HCTI-22-16.4 Signal Transformer	FIXED IND 22UH 16.4A 7 MOHM TH	657
SCIHP1367-3R3M Signal Transformer	FIXED IND 3.3UH 15A 6.8 MOHM SMD	7478
SCEP134H-1R8 Signal Transformer	FIXED IND 1.8UH 13.6A 6.6 MOHM	0
SCIHP0750-R33 Signal Transformer	FIXED IND 330NH 21A 3.7 MOHM SMD	0
HCTI-68-7.7 Signal Transformer	FIXED IND 68UH 7.7A 30 MOHM TH	40
SCIHP0750-R56 Signal Transformer	FIXED IND 560NH 19A 4.5 MOHM SMD	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