
Tyco Electronics
PolyZen Devices Polymer Protected Zener Diode
PolyZen devices are polymer enhanced precision Zener diode micro-assemblies that help protect sensitive electronics from damage caused by inductive voltage spikes, voltage transients, use of incorrect power supplies and reverse bias.
The PolyZen micro-assembly incorporates a stable Zener diode for precise voltage clamping and a resistively non-linear, polymeric positive temperature coefficient (PPTC) layer that responds to either diode heating or overcurrent events by transitioning from a low to high resistance state.
PolyZen devices help provide resettable protection against damage caused by multi-watt fault events and require only 0.7W power dissipation. In the event of sustained high power conditions, the PPTC element of the device “trips” to limit current and generate voltage drop. This functionality helps protect both the Zener and the follow-on electronics, effectively increasing the diode’s power handling capacity.
FEATUREs
• RoHS compliant
• Overvoltage transient suppression
• Hold currents up to 2.3A
• Time delayed, overvoltage trip
• Time delayed, reverse bias trip
• Power handling on the order of 30 watts
• Integrated device construction
Benefits
• Helps shield downstream electronics from overvoltage
and reverse bias
• Trip events shut out overvoltage and reverse bias
sources
• Analog nature of trip events minimize upstream
inductive spikes
• Helps reduce design costs with single component
placement and minimal heat sinking requirements
APPLICATIONs
• Portable media players
• Global positioning systems
• Hard disk drives 5V & 12V bus
• Solid State Drives (SSD) 5V bus
• Cellphone charger port and USB power
• Automotive peripheral input power
• DC power port protection
• Industrial handheld POS