| 摘要 |
PURPOSE:To stabilize the current value of a current output circuit by providing an auxiliary resistance nearby the output monitor resistance of the amplifier circuit and making the sum of heating values of the output monitor resistance and auxiliary resistance constant. CONSTITUTION:When an input is VIN, an auxiliary resistance heat generation control circuit 2 is composed of a subtracting circuit 3, adding circuit 4, multiplying circuit 5, and root circuit 6 and the respective circuits satisfy an equation I. Namely, the subtracting circuit 3 generates a function (Rc)<1/2>(b-VIN) and the adding circuit 4 generates a function (Rc)<1/2>(b+VIN); and multiplying circuit calculates Rc(b-aVIN)(b+aVIN) and the root circuit obtains {Rc(b- aVIN)(b+aVIN)}<1/2>. Resistances RM and RC are arranged very closely in contact. A ceramic substrate with good temperature characteristics is used as the substrate 7, the resistances RM and RC are formed by vapor deposition, sputtering, etc., and resistance materials use tantalum nitride. |
