Temperature Sensors - NTC Thermistors

Image	Part Number	Description / PDF	Quantity	Rfq
	B57621C683M62 TDK EPCOS	THERMISTOR NTC 68KOHM 3860K 1206	0
	B57411V2151H62 TDK EPCOS	THERMISTOR NTC 150OHM 3500K 0805	0
	B57621C332M62 TDK EPCOS	THERM NTC 3.3KOHM 3430K 1206	0
	B57621C154K162 TDK EPCOS	THERM NTC 150KOHM 4120K 1206	0
	B57621C153K62 TDK EPCOS	THERMISTOR NTC 15KOHM 3480K 1206	0
	B57331V2682K060 TDK EPCOS	THERM NTC 6.8KOHM 4390K 0603	0
	B57621C224M62 TDK EPCOS	THERM NTC 220KOHM 4120K 1206	0
	B57621C683J62 TDK EPCOS	THERMISTOR NTC 68KOHM 3860K 1206	0
	B57431V2473J062 TDK EPCOS	THERMISTOR NTC 47KOHM 0805	0
	B57411V2151J62 TDK EPCOS	THERMISTOR NTC 150OHM 3500K 0805	0
	B57621C222M62 TDK EPCOS	THERM NTC 2.2KOHM 3110K 1206	0
	B57621C334K62 TDK EPCOS	THERM NTC 330KOHM 4090K 1206	0
	B57541G1502H000 TDK EPCOS	THERMISTOR NTC 5KOHM BEAD	0
	B57551G1202H000 TDK EPCOS	THERMISTOR NTC 2KOHM BEAD	0
	B57331V2473J060 TDK EPCOS	THERMISTOR NTC 47KOHM 4390K 0603	0
	B57621C683K62 TDK EPCOS	THERMISTOR NTC 68KOHM 3860K 1206	0
	B57621C154J162 TDK EPCOS	THERM NTC 150KOHM 4120K 1206	0
	B57620C2473K62 TDK EPCOS	THERMISTOR NTC 47KOHM 0805	0
	B57550G1503H000 TDK EPCOS	THERMISTOR NTC 50KOHM BEAD	0
	B57621C332K62 TDK EPCOS	THERM NTC 3.3KOHM 3430K 1206	0

Temperature Sensors - NTC Thermistors

1. Overview

NTC (Negative Temperature Coefficient) thermistors are temperature-sensitive resistors whose resistance decreases with increasing temperature. This semiconductor ceramic device utilizes metal oxide materials to achieve precise temperature measurement and control. As a fundamental component in thermal management systems, NTC thermistors play critical roles in modern electronics, automotive engineering, and industrial automation due to their high sensitivity ( : 2000-5000 K) and accuracy ( 0.1 C to 5 C).

2. Major Types and Functional Classification

Type	Functional Characteristics	Application Examples
Bead Thermistors	Small size ( 0.5-5mm), fast response (<50ms), glass-encapsulated	Medical probes, liquid temperature monitoring
Disk Thermistors	Higher power rating, epoxy-coated, axial leads	Power supply thermal protection, HVAC systems
Chip Thermistors	SMD packaging, low profile (0.6-3.2mm), RoHS compliant	Smartphone thermal management, wearable devices
Glass-Encapsulated	Hermetic seal, corrosion resistance, operating temp: -50 C to +300 C	Automotive battery monitoring, aerospace sensors

3. Structure and Composition

Typical NTC thermistor construction includes:

Semiconductive ceramic core (Mn-Ni-Co-Ox system)
Platinum alloy electrode layers (sintered or plated)
Protective epoxy/glass encapsulation (IP67 rated)
Lead wires (Cu/Ni alloy, 26-34 AWG)

Manufacturing process involves powder synthesis at 1500 C, isostatic pressing, and controlled atmosphere sintering to achieve desired R-T characteristics.

4. Key Technical Specifications

Parameter	Description	Significance
Rated Resistance (R25)	Resistance at 25 C (100 -10M range)	System compatibility, signal conditioning design
B-Value (K)	Material constant (2000-5000K)	Determines sensitivity across operating range
Tolerance	Resistance deviation ( 1% to 15%)	Affects measurement accuracy
Operating Temp Range	-100 C to +600 C (varies by type)	Environmental suitability
Dissipation Factor	mW/ C (self-heating coefficient)	Power consumption and stability considerations

5. Application Fields

Primary industries utilizing NTC thermistors:

Industrial: Process control ( 0.5 C accuracy), motor protection
Consumer Electronics: Battery management (Li-ion charging), smart thermostats
Medical: Patient monitoring (Class F accuracy), lab equipment
Automotive: Battery pack thermal monitoring (ISO 14001 compliance), ECU protection

Notable application example: Tesla Model S battery management system uses 48-channel NTC array for cell temperature monitoring ( 1 C accuracy).

6. Leading Manufacturers and Products

Manufacturer	Key Products	Technical Highlights
Murata Electronics	NXFT Series	Automotive-grade (AEC-Q200), 0.5 C accuracy, -50 C to +150 C range
TE Connectivity	NTCLE Series	Medical certification (IEC 60601), 3.2mm chip format
Vishay Beyschlag	NTCAl Series	Aluminum housing, 50W power handling, IP68 rating

7. Selection Guidelines

Key considerations for NTC thermistor selection:

Resistance-Temperature curve matching application requirements
Environmental factors: humidity (IP rating), vibration (automotive shock specs)
Electrical parameters: operating current (self-heating effects)
Form factor constraints (SMD vs through-hole)
Calibration requirements (standard vs customized R-T tables)

Recommend verifying long-term stability (aging rate <0.2%/year) and RoHS compliance for production applications.

8. Industry Trends

Emerging developments include:

Micro-NTC fabrication (MEMS-based, <0.1mm chips)
High-temperature stability improvements (up to 600 C operation)
Integration with wireless sensor networks (Zigbee/LoRa compatibility)
AI-enhanced linearization algorithms (reducing external circuit complexity)

Market growth projected at 8.2% CAGR through 2027 driven by EV battery management demands.