| 摘要 |
<p>A buffer circuit 1 drives a capacitive load 9 based on a voltage Vin. In a setup period, switches 11 and 13 to 15 are in an ON state, and in a drive period, a switch 12 is in an ON state. A voltage comparison unit 2 compares the voltage Vin in the setup period and a voltage Vout in a drive period to output a comparison result voltage. A push-pull output unit 4 includes a TFT 25 for charge and a TFT 26 for discharge. A drive control unit 3 controls the TFTs 25 and 26 to be in an OFF state in the setup period, and in the drive period, selectively controls the TFTs 25 and 26 to be in an ON state in accordance with the comparison result voltage. If Vout < Vin, the comparison result voltage rises, the TFT 24 becomes in an ON state, a voltage at a node N6 falls, the TFT 25 becomes in the ON state, and the voltage Vout rises. Thus, there is a provided a small-sized capacitive load drive circuit with low power consumption and robust against process variation.</p> |
