SMBG12CAHE3/52

TVS - Diodes

TVS - Diodes, also known as transient voltage suppressors, are widely used for overvoltage protection. The SMBG12CAHE3/52 is a popular series of TVS-diodes that provides reliable protection for many electronic devices’ critical components. This article will discuss the application field and working principle of SMBG12CAHE3/52.

Application Field

The SMBG12CAHE3/52 is a bidirectional TVS diode designed for low reverse power dissipation (Pd = 5W), high peak surge current handling (Ipp = 40A) and a reverse working voltage of 8V. The SMBG12CAHE3/52 is used in various protection circuits, including:

• High-side switch modules
• Back-up time controllers
• High frequency switching converter circuits
• Battery charging port protection
• Data interfaces and cabling networks
• Power pads on printed circuit boards (PCBs)
• Computer equipment and peripherals

Working Principle

The working principle of the SMBG12CAHE3/52 TVS-diode can be explained in three primary steps.

Step 1: Clamping Voltage

The SMBG12CAHE3/52 is a bidirectional avalanche-rated diode that offers extremely high-current protection for both positive and negative overvoltage events. When an overvoltage is present at the protected component, the diode’s junction capacitance stores the energy of the excessive charge. The stored energy is then converted into a rapidly increasing current pulse. This process is known as “avalanche breakdown”.

Step 2: Clamping Action

The avalanche breakdown process causes the diode’s internal resistance to rapidly increase, limiting the current until the overvoltage conditions are corrected. This is referred to as “clamping action.” It prevents the destructive current from flowing into the protected component, thus protecting it from damage or destruction.

Step 3: Re-Establishing the Normal Voltage

Once the overvoltage is corrected, the electrical current flows through the diode’s P-N junction in the opposite direction, restoring the voltage to the original level. This re-establishes the normal electrical conditions, allowing the protected component to continue to function normally.

Conclusion

The SMBG12CAHE3/52 is a powerful and reliable TVS-diode system that offers protection to sensitive components in a variety of applications. Its three-step process provides reliable protection against overvoltage, while also allowing for normal operation to be re-established quickly and easily.