This part is a kind of semiconductor called 1SMA14CAT3G.

Function of this product has 400 Watt Peak Power Zener Transient Voltage Suppressors.

Manufacturers : ON Semiconductor

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1SMA10CAT3G Series, SZ1SMA10CAT3G Series 400 Watt Peak Power Zener Transient Voltage Suppressors Bidirectional The SMA series is designed to protect voltage sensitive components from high voltage, high energy transients. They have excellent clamping capability, high surge capability, low zener impedance and fast response time. The SMA series is supplied in ON Semiconductor’s exclusive, cost-effective, highly reliable SURMETIC package and is ideally suited for use in communication systems, automotive, numerical controls, process controls, medical equipment, business machines, power supplies and many other industrial/consumer applications. Features  Working Peak Reverse Voltage Range − 10 V to 78 V  Standard Zener Breakdown Voltage Range − 11.7 V to 91.3 V  Peak Power − [ ... ]

1SMA14CAT3G PDF Datasheet Download