Integrated injection logic or merged transistor logic is a novel bipolar circuit design approach to achieve high-density large-scale integration. As the basic logic units it uses multicollector npn transistors which are powered from merged multicollector lateral pnp transistors. I2L can be fabricated with standard buried collector technology and is therefore compatible with conventional bipolar circuitry on the same chip. The feature of having special interface circuitry—digital and/or linear—on the same chip renders I2L a powerful LSI technique.