| 摘要 |
PURPOSE:To prevent the influence of dispersion in the gate lengths of transistors caused by manufacture dispersion. CONSTITUTION:Various circuits such as a doubler, differential amplifier, multiplier and pseudo logarithm amplifier or the like to be realized by an MOS integrated circuit are composed based on the differential circuit shown in the figure. For this differential circuit, a differential pair is composed of an (m) number of transistors (M1-Mm) respectively connecting drains, gates and sources in common and an (n) number of transistors (Mm-1-Mm-n) respectively connecting drains, gates and sources in common. The respective transistors are formed in the same dimension and the accuracy of output currents (IOUT and IOUT') is decided by a ratio m/n. Since the (m) and (n) are arbitrary integers the ratio is a fixed value. Therefore, the ratio m/n can be defined as a constant not affected by the dispersion in the gate lengths or the gate width caused by the manufacture dispersion of the transistors. |
