| 摘要 |
Dynamic range of a differential pixel is enhanced by injecting, synchronously or asynchronously, a compensating offset (Delta<SUB>COMP</SUB>) into a differential signal capacitor whenever magnitude of the differential signal across the capacitor exceeds a predetermined value. Positive and negative magnitudes of Delta<SUB>COMP </SUB>need not be equal. The number (N) of Delta<SUB>COMP </SUB>offsets made is counted. Effective differential signal capacitor voltage V(t)=Vo±N.Delta<SUB>COMP</SUB>, where Vo is capacitor voltage. In other embodiments magnitude of Delta<SUB>COMP </SUB>in a sequence of compensations can differ, and the sum total of compensations in recorded. Differential pixel signal/noise ratio is increased by dynamically maximizing operational amplifier gain A<SUB>G </SUB>for each differential pixel.
|
