| 摘要 |
PURPOSE:To suitably switch a current with a simple circuit by generating a base control signal of a transistor for switching the current by an amplified controlled in the gain and the output operating range by a current proportional to an input current amount. CONSTITUTION:After the output of a Hall element is amplified by a differential amplifier which has transistors 5, 6 inputting the output of the Hall element, a transistor 18 and a resistor 20, it is supplied to the bases of transistors 2, 3 which form a switch circuit. A current source of the differential amplifier, i.e., the current amount of a current source which has the transistor 18 and the resistor 20 is varies proportionally to the current amount input to the transistors 2, 3. When thus constructed, the amplitude of a switching signal input to the bases is varied proportionally to the current supplied to the common emitter of the transistors 2, 3 which form a switch circuit. |
