When you are designing a board with limited space, but need to build in reliable resettable circuit protection, PolySwitch surface-mount products can help. With continued miniaturization and increased functionality of electronic products we understand your need for smaller more robust circuit protection that will help you meet the increasingly stringent agency requirements. We offer the widest variety of PPTC surface-mount devices in the industry with our Raychem Circuit Protection surface-mount line. We now offer automotive specific surface-mount devices (miniSMD, nanoSMD, AHS, and ASMD devices) that have been tested to the AECQ200 standard. See the PolySwitch Automotive Devices section for more information.
* Devices tested to the AECQ200 standard ** * Maximum resistance is measured 1 hour after reflow RoHS Compliant
Part Numbering System for PolySwitch Surface-mount Devices
Agency Recognition for PolySwitch Surface-mount Devices
Standard
Parts
File Number
UL
all PolySwitch surface-mount devices
E74889
CSA
all PolySwitch surface-mount devices
CA78165
TÜV
microSMD and miniSMD series
R72041438
TÜV
nanoSMD series
R72041439
TÜV
SMD series
R72041427
TÜV
decaSMD series
R72090019
TÜV
SMDH series
R72072048
TÜV
picoSMD series
R72072068
Solder Reflow and Rework Recommendations for PolySwitch Surface-mount Devices
Recommended reflow methods:
•IR
•Hot air
•Nitrogen
Recommended maximum paste thickness: 0.25mm (0.010 inch)
Recommendations:
Devices can be cleaned using standard methods and aqueous solvents.
Tyco Electronics believes that the optimum conditions for forming acceptable solder fillets occur when a reasonable amount of solder paste is placed underneath each device's termination. As such, Tyco Electronics requests that customers comply with our recommended solder pad layouts.
Customer should validate that the solder paste amount and reflow recommendations meet the application.
Tyco Electronics requests that customer board layouts refrain from placing raised features (e.g. vias, nomenclature, traces, etc.) underneath PolySwitch devices. It is possible that raised features could negatively impact solderability performance of our devices.
Rework
• picoSMD, nanoSMD, microSMD and miniSMD series: standard industry practices . Please also avoid direct contact to the device.
•SMD series: rework should be confined to removal of the installed product and replacement with a fresh device.
Classification Reflow Profiles
Profile Feature
Sn-Pb Eutectic Assembly
Pb-Free Assembly
Average Ramp-Up Rate (Tsmax to Tp)
3 °C/second max.
3° C/second max.
Preheat
• Temperature Min (Tsmin)
100 °C
150 °C
• Temperature Max (Tsmax)
150 °C
200 °C
• Time (tsmin to tsmax)
30-70 seconds
30-70 seconds
Time maintained above:
• Temperature (TL)
183 °C
217 °C
• Time (tL)
60-150 seconds
60-150 seconds
Peak/Classification Temperature (Tp)
240 °C
260 °C
Time within 5 °C of actual Peak
Temperature (tp)
10-30 seconds
20-40 seconds
Ramp-Down Rate
6 °C/second max.
6 °C/second max.
Time 25 °C to Peak Temperature
6 minutes max.
8 minutes max.
Note: All temperatures refer to topside of the package, measured on the package body surface.
Operation beyond the maximum ratings or improper use may result in device damage and possible electrical arcing and flame.
The devices are intended for protection against occasional overcurrent or overtemperature fault conditions and should not be used when repeated fault conditions or prolonged trip events are anticipated.
Contamination of the PPTC material with certain silicon based oils or some aggressive solvents can adversely impact the performance of the devices.
Device performance can be impacted negatively if devices are handled in a manner inconsistent with recommended electronic, thermal, and mechanical procedures for electronic components.
Operation in circuits with a large inductance can generate a circuit voltage (L di/dt) above the rated voltage of the PolySwitch resettable device.
When you are designing a board with limited space, but need to build in reliable resettable circuit protection, PolySwitch surface-mount products can help. With continued miniaturization and increased functionality of electronic products we understand your need for smaller more robust circuit protection that will help you meet the increasingly stringent agency requirements. We offer the widest variety of PPTC surface-mount devices in the industry with our Raychem Circuit Protection surface-mount line. We now offer automotive specific surface-mount devices (miniSMD, nanoSMD, AHS, and ASMD devices) that have been tested to the AECQ200 standard. See the 
