Temperature Sensors - PTC Thermistors

Image Part Number Description / PDF Quantity Rfq
B59300M1070A70

B59300M1070A70

TDK EPCOS

THERMISTOR PTC 300 OHM RADIAL

0

B59310U1140B70Z15

B59310U1140B70Z15

TDK EPCOS

PTC THERMISTOR

0

B59313U1130B70Z5

B59313U1130B70Z5

TDK EPCOS

PTC THERMISTOR

0

B59048B1080B151Z

B59048B1080B151Z

TDK EPCOS

PTC THERMISTOR

0

B59313U1160B70Z15

B59313U1160B70Z15

TDK EPCOS

PTC THERMISTOR

0

B59546A135A20V61

B59546A135A20V61

TDK EPCOS

PTC THERMISTOR

0

B59151U1130B70Z

B59151U1130B70Z

TDK EPCOS

PTC THERMISTOR

0

B59310U1180B70Z5

B59310U1180B70Z5

TDK EPCOS

PTC THERMISTOR

0

B59536A135A20V1

B59536A135A20V1

TDK EPCOS

PTC THERMISTOR

0

B59314U1160B70Z

B59314U1160B70Z

TDK EPCOS

PTC THERMISTOR

0

B59148A270A10

B59148A270A10

TDK EPCOS

PTC THERMISTOR

0

B59115J140A20

B59115J140A20

TDK EPCOS

PTC THERMISTOR

0

B59525T1120A62

B59525T1120A62

TDK EPCOS

THERMISTOR PTC 25 OHM 20% 4SMD

0

B59171U120B70

B59171U120B70

TDK EPCOS

PTC THERMISTOR

0

B59001U1090B70V30

B59001U1090B70V30

TDK EPCOS

PTC THERMISTOR

0

B59251U1080B70

B59251U1080B70

TDK EPCOS

PTC THERMISTOR

0

B59078U1150B70Z

B59078U1150B70Z

TDK EPCOS

PTC THERMISTOR

0

B59095U1145B70Z15

B59095U1145B70Z15

TDK EPCOS

PTC THERMISTOR

0

B59670A1080B10V1

B59670A1080B10V1

TDK EPCOS

THERMISTOR PTC

0

B59451C1130B770Z15

B59451C1130B770Z15

TDK EPCOS

THERMISTOR PTC

0

Temperature Sensors - PTC Thermistors

1. Overview

Positive Temperature Coefficient (PTC) thermistors are resistors with a positive temperature coefficient, meaning their resistance increases significantly with temperature rise. Unlike NTC thermistors, PTC devices exhibit a sharp resistance transition at a critical temperature (Curie point). They are widely used in overtemperature protection, self-regulating heating elements, and temperature sensing applications. Their inherent safety features and reliability make them critical components in modern electronics, automotive systems, and industrial equipment.

2. Main Types and Functional Classification

TypeFunctional CharacteristicsApplication Examples
Ceramic PTC ThermistorsHigh Curie temperature, abrupt resistance change, durableOverheat protection in motors, heaters, and power supplies
Polymer PTC ThermistorsLower switching temperature, resettable fuse functionalityUSB port protection, battery management systems
Switching PTCDigital on/off behavior at threshold temperatureThermal cutoff for appliances, HVAC systems
Linear PTCProportional resistance-temperature responsePrecision temperature measurement in industrial controllers

3. Structure and Composition

PTC thermistors typically consist of polycrystalline ceramic semiconductor materials (e.g., BaTiO3 doped with rare earth elements) with embedded silver or platinum electrodes. The core structure includes: - Semiconductor ceramic body with tailored Curie temperature - Metal electrodes for electrical connection - Protective epoxy or glass coating - Lead wires (axial/radial) or SMD terminations The PTC effect arises from the material's phase transition at Curie temperature, causing resistance spikes due to crystal lattice changes.

4. Key Technical Specifications

ParameterDescriptionImportance
R25 (Resistance at 25 C)Baseline resistance valueDetermines circuit compatibility
Tswitch (Switching Temperature)Critical temperature for resistance jumpApplication-specific threshold setting
Rmin/Rmax RatioResistance range spanIndicates sensitivity and switching capability
Dissipation Factor (mW/ C)Power dissipation per temperature unitAffects thermal response speed
Response Time (ms)Time to reach 90% resistance changeCritical for real-time protection systems

5. Application Fields

Major application sectors include: - Consumer Electronics: Smartphones (battery protection), 3D printers (hotend monitoring) - Automotive: EV battery thermal management, seat heater control - Industrial: Motor overload protection, pipeline freeze detection - Renewable Energy: Solar charge controllers, wind turbine gear monitoring - Medical: Patient warming systems, diagnostic equipment thermal regulation

6. Leading Manufacturers and Products

ManufacturerKey ProductsFeatures
Vishay BeyschlagK2500-FinderAutomotive-grade PTC with 50-150 C range
TE ConnectivityPS224-202UL-certified resettable fuse for power supplies
Murata ElectronicsPXU11S150R0Miniature SMD PTC for IoT devices
EPCOS (TDK)B59904C0150A070High-current PTC for industrial motor protection

7. Selection Guidelines

Key selection criteria: - Required switching temperature vs operating temperature range - Resistance tolerance and stability over lifespan - Package type (through-hole, SMD, bolt-on) - Voltage/current ratings with safety margin - Compliance with standards (UL, RoHS, AEC-Q200 for automotive) - Environmental resistance (humidity, vibration, chemical exposure)

8. Industry Trends

Emerging trends include: - Development of nano-ceramic materials for faster response times (<10ms) - Integration with MEMS technology for IoT sensor nodes - Higher temperature stability beyond 200 C for e-mobility applications - Miniaturization to 0402 SMD package sizes - AI-based predictive thermal management systems using PTC arrays - Increased adoption in hydrogen fuel cell thermal monitoring systems

RFQ BOM Call Skype Email
Top