| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a constant voltage circuit for supplying a constant voltage in which dependency of a field effect transistor on a threshold voltage is suppressed. <P>SOLUTION: A constant voltage circuit of the present invention comprises: field effect transistors Q11 and Q12 whose drains are commonly connected at a first node and whose gates are commonly connected at a second node; a resistor R11 connected between the second node at which the gates of the field effect transistors Q11 and Q12 are commonly connected and a source of the field effect transistor Q12; a bipolar transistor Q13 whose collector is connected to the second node; a bias circuit 101, connected to the source of the field effect transistor Q12, for supplying a bias voltage to a base of the bipolar transistor Q13. In the constant voltage circuit, a voltage source Vbat is connected to the first node at which the drains of the field effect transistors Q11 and Q12 are commonly connected, and a constant voltage is supplied from a source of the field effect transistor Q11. <P>COPYRIGHT: (C)2012,JPO&INPIT |
