The BD679AS is a medium power NPN Darlington transistor in a TO-126 package. It features a collector-emitter voltage of 80V and a continuous collector current rating of 4A, with a peak capability of 6A. This device offers a high DC current gain of at least 750 and a total power dissipation of 40W at a 25°C case temperature. Its characteristics make it suitable for a variety of medium power linear and switching applications, such as amplifier stages and power control circuits.