Class AB Differential Stage on Complementary Field-Effect Transistors (CJFET, CCMOS) and Inclusion Schemes in Micro-Power High-Speed Operational Amplifiers

A new class AB differential stage architecture based on complementary field effect transistors with control p-n junction (CJFets) is considered, which does not contain reference current sources in the source circuits of the input transistors. This circuit design technique allows the slew rate of micro-power operational amplifiers (OAs) to be increased many times over in both non-inverting and inverting configurations. The elimination of reference current sources in the OA input stage, as shown by the results of theoretical analysis and modeling, has a positive effect on the numerical values of the systematic component of the zero offset voltage, which has extremely small values for ideal current mirrors. As an example, a OA circuit realized on CJFet and CBJT active elements from Intersil Corporation is given. The results of computer modeling of the OA statics at different widths and lengths of JFet channels are presented. The discussed circuit design technique is recommended for practical use in high temperature analog microcircuits on SiC and GaN wide gap semiconductors.