| 摘要 |
PURPOSE:To obtain a drive circuit with less output capacitance dependancy, less output residual voltage and capable of driving a load at high speed by providing plural stages of CMOS output buffers driven with an output voltage from a resistive load. CONSTITUTION:An input Vin is fed to a transistor (TR)Q18 of a driver circuit 3 via a differential switch circuit 1 and a level shifter 2, and when the input Vin is at H level, a TRQ15 is turned on and an output Vout is outputted via two stages of CMOS buffers 4a, 4b. A resistor R18 is selected to a high resistance so as to suppress the deep saturation of the TRQ15, and the gain of the output Vout is increased to the input Vin by setting a W/L (where, W is the gate width and L is the gate length) of the CMOS output buffer to a large value. Further, the response speed is quickened by providing two stages of buffers with different W/L, the output capacitance C11 is charged and discharged at high speed and the load RL is driven at high speed. |
