| 摘要 |
PURPOSE:To obtain a comparator whose comparison time is reduce by applying positive feedback to an inverting input terminal of a differential amplifier. CONSTITUTION:When switches S5, S6 are changed from the on-state to the off-state, the 1st differential amplifier A1 detects a difference between an input voltage Vin and a reference voltage VR, it output Q(=Vout1) changes toward mu1(Vin-VR), the 2nd differential amplifier A2 detects a difference between the output Vout1 of the 1st differential amplifier A1 and the reference voltage VR and its output Q(Vout2) changes toward -mu2(Vout1-VR). When the 1st and 4th switches S1 and S4 are changed from the on-state to the off-state and the 2nd and 3rd switches S2 and S3 are changed from the off-state into the on-state, positive feedback is applied to the 1st differential amplifier A1 from both the non-inverting input terminal and the inverting input terminal, its output Q changes toward mu1(Vout1-Vout2) at a high speed up to the maximum operating voltage Vmax1, made stable at the voltage, and on the other hand, the output Q of the 2nd differential amplifier A2 changes up to the maximum operating voltage Vmax2 at a high speed and is made stable at the voltage. |
