| Image | Part Number | Description / PDF | Quantity | Rfq |
|---|---|---|---|---|
 |
TDK EPCOS |
THERMISTOR PTC 470 OHM 50% 0603 |
7895 |
|
 |
TDK EPCOS |
THERMISTOR PTC 4.7 OHM 20% DISC |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 3.2 OHM 50% RECT |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 3.2 OHM 50% RECT |
1205 |
|
 |
TDK EPCOS |
THERMISTOR PTC 55 OHM 15% DISC |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 1K OHM 50% RECT |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 4.6 OHM 25% SMD |
573 |
|
 |
TDK EPCOS |
THERMISTOR PTC 9 OHM 30% DISC |
386 |
|
 |
TDK EPCOS |
THERMISTOR PTC 680 OHM 50% 0805 |
4460 |
|
 |
TDK EPCOS |
THERMISTOR PTC 45 OHM 20% DISC |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 3.5K OHM 30% RAD |
1709 |
|
 |
TDK EPCOS |
THERMISTOR PTC 100 OHM |
8464 |
|
 |
TDK EPCOS |
THERMISTOR PTC 700 OHM 50% RECT |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 100 OHM |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 1.3K OHM 50% RECT |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 1.5K OHM 25% RAD |
0 |
|
 |
TDK EPCOS |
THERMISTOR PTC 700 OHM 50% RECT |
551 |
|
 |
TDK EPCOS |
PTC THERMISTOR |
2025 |
|
 |
TDK EPCOS |
THERMISTOR PTC 680 OHM 50% 0805 |
5412 |
|
 |
TDK EPCOS |
THERMISTOR PTC 4.2K OHM 35% COIN |
0 |
|
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.
| Type | Functional Characteristics | Application Examples |
|---|---|---|
| Ceramic PTC Thermistors | High Curie temperature, abrupt resistance change, durable | Overheat protection in motors, heaters, and power supplies |
| Polymer PTC Thermistors | Lower switching temperature, resettable fuse functionality | USB port protection, battery management systems |
| Switching PTC | Digital on/off behavior at threshold temperature | Thermal cutoff for appliances, HVAC systems |
| Linear PTC | Proportional resistance-temperature response | Precision temperature measurement in industrial controllers |
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.
| Parameter | Description | Importance |
|---|---|---|
| R25 (Resistance at 25 C) | Baseline resistance value | Determines circuit compatibility |
| Tswitch (Switching Temperature) | Critical temperature for resistance jump | Application-specific threshold setting |
| Rmin/Rmax Ratio | Resistance range span | Indicates sensitivity and switching capability |
| Dissipation Factor (mW/ C) | Power dissipation per temperature unit | Affects thermal response speed |
| Response Time (ms) | Time to reach 90% resistance change | Critical for real-time protection systems |
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
| Manufacturer | Key Products | Features |
|---|---|---|
| Vishay Beyschlag | K2500-Finder | Automotive-grade PTC with 50-150 C range |
| TE Connectivity | PS224-202 | UL-certified resettable fuse for power supplies |
| Murata Electronics | PXU11S150R0 | Miniature SMD PTC for IoT devices |
| EPCOS (TDK) | B59904C0150A070 | High-current PTC for industrial motor protection |
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)
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