Semiconductor integrated circuit device with internal potential generating circuit allowing external tuning of internal power supply potential

A semiconductor integrated circuit device comprising:

• at least one internal circuit for performing predetermined processing based on at least data applied externally with respect to said semiconductor integrated circuit device or data transmitted mutually;
• an internal potential generating circuit provided corresponding to said internal circuit for receiving a level set signal including information representing a level of an internal potential, and producing an internal potential at a level corresponding to said level set signal;
• said internal potential generating circuit including:
• a comparing circuit operating in a normal operation to compare said internal potential generated by said internal potential generating circuit with the level corresponding to said level set signal, and operating in a test operation to stop the comparison between the level corresponding to said level set signal and said internal potential, and to compare a comparison reference potential with the level corresponding to said level set signal, and
• a potential control circuit for tuning the level of said internal potential in accordance with an output of said comparing circuit;
• a test control circuit for controlling test processing of a level of the output potential of said internal potential generating circuit, and operating in said test operation to apply successively the plurality of level set signals to said internal potential generating circuit for successively generating the plurality of internal potentials at different levels, respectively;
• a measuring circuit performing measurement in said test operation for detecting a set value required in said level set signal based on results of the comparison by said comparing circuit between the respective internal potentials generated by said internal potential generating circuit and said comparison reference potential;
• and
• a transmitting circuit for transmitting results of the measurement of said measuring circuit to said test control circuit.