| 摘要 |
PURPOSE:To obtain a reference voltage whose temperature dependency is small by inserting a transistor and a resistance into a band gap type constant-current circuit, fetching the base potential of its transistor by combining a diode, and outputting it by an emitter follower. CONSTITUTION:When a ratio of emitter areas of transistors 19, 20, a value of a resistance 21, and a value of a resistance 18 are denoted as (n), R1, and R2, and values of resistances 13, 14 are equal, an emitter potential V1 of a transistor 17 is given as an expression I. A temperature coefficient of this potential V1 is given by an expression II, therefore, the temperature coefficient can be set to '0' by selecting suitably R2/R1. This voltage is fetched by using the base of the transistor 17, a diode 9 and resistances 10, 11, applied to a transistor 2, and outputted by an emitter follower. |
