| 摘要 |
An amplifier circuit uses capacitor as voltage sources so that the amplifier can achieve high precision gain without either ratioed capacitors or absolute value of capacitors or resistors. In one embodiment, the amplifier circuit includes two or more capacitors that are each charged up to the input voltage during the sample phase. Then, during the hold phase, the switching network operates to connect the two or more capacitors in series between the input and output terminals of an operational amplifier, thereby generating an output voltage being N times the input voltage, N being the total number of capacitors connected in series. The amplifier circuit of the present invention is capable of achieving very high precision gain with very high slew rate. In particular, the amplifier circuit achieves very accurate integer gain (1x, 2x, 3x, and so on). Fractional gains can also be obtained with the use of a ratioed capacitor.
|
