MSMLG43A/TR Circuit Protection

Transient Voltage Suppressor (TVS) Diodes are designed to protect sensitive electronic components from voltage transients induced by lightning and other transient voltage events. The MSMLG43A/TR is a surface mount TVS diode specifically designed for the automotive market in order to protect the electronics in vehicles from such events. This article discusses the application field and working principle of the MSMLG43A/TR.

Application Field

The MSMLG43A/TR TVS diode is designed to provide transient over-voltage protection in automotive and distributed applications. It has been specifically designed for applications that require low clamping voltage and a high surge capability. The device is especially suitable for applications that provide over-voltage protection from events such as radiated electromagnetic fields (EMF), electrostatic discharge (ESD) and unbalanced power lines. Furthermore, the device is compatible with board-level EMC and ESD tests.

Features

The device offers an array of features designed to meet the stringent demands of the automotive industry. These include a low capacitance (1250pF) to ensure low insertion loss, a low leakage current (2.5uA), a very low maximum clamping voltage (19.0V), and a very fast reaction time (30 nano-seconds). It is also available in a surface-mount SOT-23 package, making it ideal for integration into PCB designs.

Working Principle

The MSMLG43A/TR TVS diode operates by clamping transients in the supply or input line to ground. It is designed to be connected in parallel with the circuit that needs to be protected. When the surge voltage exceeds the breakdown voltage of the diode, it begins to conduct. This redirects the surge current through the diode, thus limiting the voltage across the protected device. The device is designed to operate in a bi-directional mode, meaning that it can protect the device from both positive and negative over-voltages. When the voltage returns to normal levels, the device re-opens and the protected circuitry is released from the low clamp voltage.

Conclusion

The MSMLG43A/TR is a surface-mount TVS diode designed specifically for automotive applications. It is designed to provide low-clamping voltage and a high surge capability to protect sensitive electronic components from voltage transients. The device operates by redirecting surge current through itself, thus limiting the voltage across the device that needs to be protected. It is also designed to be compatible with board-level EMC and ESD testing.