| 摘要 |
PURPOSE:To obtain a sensing circuit for multi-value signal charge which can detect the signal charge having multi-value, by providing a comparing means which compares the unknown potential corresponding the charge quantity to be inspected with plural reference potentials and then offers the detecting signal obtained at a time point when the level relation reverses between said unknown potential and plural reference potentials. CONSTITUTION:The potential PX produced at a signal sensing node is proportional to the charge quantity QX supplied to a capacitor CX. While the potential PSN produced at a reference node is proportional to the charge quantity QSN supplied to a capacitor CS. A comparing circuit 38 compares the potential PX with the potential PSN and discriminates difference between them. The comparison output signal e1 of the circuit 38 obtained from the discrimination of comparison is fed to an AND gate circuit 42 in the form of the gate signal e2. Then the AND signal e3 of the signal e2 and the signal phi6 is delivered from the circuit 42. From the result of comparison, the value corresponding to the value of the charge to be inspected is decided among N values to obtain the information showing the value of the charge to be inspected. |
