How do "avalanche breakdown diodes" protect against electrostatic discharge (ESD)?
1 Answer
Avalanche breakdown diodes, commonly known as Zener diodes or Zener voltage regulators, are not typically used for protecting against electrostatic discharge (ESD). Instead, they are primarily employed as voltage regulators and in voltage reference applications.
For ESD protection, devices such as Transient Voltage Suppressor (TVS) diodes are commonly used. TVS diodes are designed to handle transient voltage spikes, such as those produced during an ESD event, and protect sensitive electronic components from damage. They have a very fast response time and can dissipate high levels of transient energy.
Here's a brief explanation of how TVS diodes work in ESD protection:
Reverse breakdown mechanism: TVS diodes are designed to have a low breakdown voltage in the reverse-biased direction. When the voltage across the diode exceeds the breakdown voltage, the diode enters a state of rapid and controlled conduction. This allows excess current from the ESD event to be diverted away from the sensitive circuitry and safely dissipated through the diode.
Fast response time: TVS diodes have a very fast response time, typically in the order of picoseconds or nanoseconds. This quick response ensures that they begin conducting and clamping the voltage before it can reach levels that could potentially damage the protected components.
Reusability: TVS diodes are designed to handle multiple ESD events without being permanently damaged. They can absorb the transient energy and return to their non-conducting state after the event, ready to protect against subsequent discharges.
It's important to choose the appropriate TVS diode with suitable voltage ratings, response times, and power handling capabilities to effectively protect sensitive electronic components from ESD events. Additionally, ESD protection usually involves a combination of design practices, grounding techniques, and component selection to ensure comprehensive protection throughout the entire electronic system.
For ESD protection, devices such as Transient Voltage Suppressor (TVS) diodes are commonly used. TVS diodes are designed to handle transient voltage spikes, such as those produced during an ESD event, and protect sensitive electronic components from damage. They have a very fast response time and can dissipate high levels of transient energy.
Here's a brief explanation of how TVS diodes work in ESD protection:
Reverse breakdown mechanism: TVS diodes are designed to have a low breakdown voltage in the reverse-biased direction. When the voltage across the diode exceeds the breakdown voltage, the diode enters a state of rapid and controlled conduction. This allows excess current from the ESD event to be diverted away from the sensitive circuitry and safely dissipated through the diode.
Fast response time: TVS diodes have a very fast response time, typically in the order of picoseconds or nanoseconds. This quick response ensures that they begin conducting and clamping the voltage before it can reach levels that could potentially damage the protected components.
Reusability: TVS diodes are designed to handle multiple ESD events without being permanently damaged. They can absorb the transient energy and return to their non-conducting state after the event, ready to protect against subsequent discharges.
It's important to choose the appropriate TVS diode with suitable voltage ratings, response times, and power handling capabilities to effectively protect sensitive electronic components from ESD events. Additionally, ESD protection usually involves a combination of design practices, grounding techniques, and component selection to ensure comprehensive protection throughout the entire electronic system.