| 摘要 |
PURPOSE:To supply a stable current with high accuracy by cancelling the temperature coefficient dof a transistor with the temperature characteristic of a base current source and forming an emitter area into a prescribed multiple of an emitter area of a series diode to suppress the variation of a current amplification factor. CONSTITUTION:A correction circuit 7 has a current path 7a comprising an NPN transistor (TR)72 and a resistor 73 and a current path 7b comprising a resistor 74, the former path has a positive temperature coefficient and the latter has a negative temperature coefficient to cancel the positive temperature coefficient of an NPN TR15a of an output stage through the constitution. Moreover, the ratio of the base currcent flowing to the NPN TR15 to the current I1 flowing a series diode 32 is set geometrically by the emitter area and the current mirror circuit 33 stablizes the current I2. As a result, a collector-emitter voltage of the TR15a is set to nearly 1-1.4V to absorb the fluctuation of the power supply voltage. |
