Temperature Sensors - NTC Thermistors

Part Number	Description / PDF	Quantity
B57540G1503H005 TDK EPCOS	THERMISTOR NTC 50KOHM 3973K BEAD	0
B57560G1103F005 TDK EPCOS	THERMISTOR NTC 10KOHM 3612K BEAD	830
B57550G1203F000 TDK EPCOS	THERMISTOR NTC 20KOHM 3992K BEAD	0
B57565G1103G000 TDK EPCOS	THERMISTOR NTC 10KOHM 3478K BEAD	0
B57871S0103F251 TDK EPCOS	THERMISTOR NTC 10KOHM 3988K BEAD	0
B57025M2103A001 TDK EPCOS	THERM NTC 10KOHM 3980K NONSTND	135
B57560G0503H000 TDK EPCOS	THERMISTOR NTC 50KOHM 3992K BEAD	0
B57540G1104G002 TDK EPCOS	THERM NTC 100KOHM 4072K BEAD	0
B57560G145F TDK EPCOS	THERM NTC 1.4MOHM 4557K BEAD	0
B57561G1303F005 TDK EPCOS	THERMISTOR NTC 30KOHM 3940K BEAD	0
B57891M0474K052 TDK EPCOS	THERM NTC 470KOHM 5000K DISC	0
B57881S0103J251 TDK EPCOS	THERMISTOR NTC 10KOHM 3980K DISC	0
B57891M0502J055 TDK EPCOS	THERMISTOR NTC 5KOHM DISC	0
B57891S0103J853 TDK EPCOS	THERMISTOR NTC 10KOHM 3950K DISC	0
B57561G1303H005 TDK EPCOS	THERMISTOR NTC 30KOHM 3940K BEAD	0
B57220K333J TDK EPCOS	THERMISTOR NTC 33KOHM 3560K COIN	0
B57431V2104J072 TDK EPCOS	THERM NTC 100KOHM 4390K 0805	0
B57881S0212H051 TDK EPCOS	THERM NTC 2.1KOHM 3560K DISC	0
B57891M1102J001 TDK EPCOS	THERMISTOR NTC 1KOHM 3930K DISC	0
B57891M534J52 TDK EPCOS	THERMISTOR NTC 530KOHM DISC	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.