Abstract: A source follower current steering logic circuit useful in, for example, fabricating digital integrated logic circuits using gallium arsenide and current mode logic switches. The circuit includes an input logic network which includes level shifting networks to generate output signals having assertion levels of different voltage levels and a reference voltage logic network having a similar level shifting network for generating reference voltages relative to the voltage levels of the assertion levels of the output signals from the input logic network. A logic tree includes current mode logic switches for receiving the output signals from the input logic network and the reference voltage generating network to perform selected logic operations the output signals. The output signals are taken from the logic tree. A top load clamps the output signals to selected voltage levels.