| 摘要 |
PURPOSE:To obtain a constant current source by setting the distance between gate and source so that a parasitic resistor equal to VGS/ID wherein the drain current and the value at the intersection of the chracteristic curves of the voltage between gate and source that are obtained when ambient temperature is changed with the voltage between drain and source kept constant are ID and VGS1 respectively may be formed between gate and source. CONSTITUTION:When ambient temperature is changed with the voltage between drain and source kept constant, the chracteristic curves of the drain current - voltage between gate and source intersect each other almost at a point (ID, VGS1), and the variation of drain current by temperature is minimum at the point. By utilizing this, voltage VGS1 and current ID can be maintained at selt-saturation bias at a source earthing type circuit by means of a resistor RS. The setting of said resistor RS can be made in terms of the distance between gate and source layer. |
