Abstract: Practical structures of an ultra large scale semiconductor integrated (ULSI) circuit especially a dynamic random access memory of 16 M bits or more are involved. The ULSI circuit uses internal operating voltages and how to construct a reference voltage generating circuit and a voltage limiter circuit in the ULSI circuit is a matter of importance. The operation of the reference voltage generating circuit and voltage limiter circuit can be stabilized, characteristics of these circuits are improved, and layout of these circuits as applied to memory cell array, peripheral circuits and the like can be improved. Improved methods of testing these circuits are provided.