| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a voltage amplifier capable of amplifying input signals having a variety of signal amplitudes to have a certain amplitude by using a reference voltage circuit having an excellent response performance. <P>SOLUTION: In a reference voltage generation circuit 7, only a switch SW1 is turned off in a first period and a maximum peak value Vmax of an input signal In is kept at a node A of a first capacitor 1. In the next second period, switches SW2 and SW3 are released and a voltage difference of the maximum peak value V max and a minimum peak value Vmin is held at a node C of a capacitor array 4. At this time, a holding voltage of a second capacitor 2 in the capacitor array 4 is added to a holding voltage of a first capacitor 1, and a voltage of a node B is outputted as a reference voltage Vref. The input signal In is given to one input terminal of a differential amplification circuit 6, and the reference voltage Vref is given to the other input terminal. The reference voltage Vref is generated at a point of time when the holding voltages of the nodes A and C are stabilized. <P>COPYRIGHT: (C)2008,JPO&INPIT |
