| 摘要 |
PURPOSE:To relieve threshold voltage from its temperature-dependency by a method wherein the potential of a semiconductor substrate is varied with substrate temperatures. CONSTITUTION:A substrate potential setting circuit 1 is formed on an Si substrate by making P-N junction diodes 3 in 4-stage series in a forward direction, and a resistor 4 in series. This device is used by connecting a terminal 5 to the ground, and a terminal 6 to the negative bias. Substrate voltages are supplied to the FET of a block 2 through an output terminal 7. With such a construction, the substrate potential is controlled with substrate temperatures, and VT variations generated in the variation in substrate temperature are corrected by utilizing substrate bias effect. This method makes the FET2 before temperature compensation temperature-dependent in threshold voltage at approx. dVT/dTapprox.=-1.8mV/ deg.C in a using set temperature range of -30-+70 deg.C, but the width of VT variation under temperature compensation reduced to 20mV by a factor of 1/9 compared with the variation width 180mV of a MOSFET without compensation. |
