| 摘要 |
An integrator circuit is connected to a capacitor that is to be measured and the capacitor driven by a read pulse. A first switch grounds the integrator input between read pulses and a second switch applies a bias input to the integrator. The bias is selected so that the integrator is active and its output high. Then, during the read pulse interval, the integrator will hold its input close to ground so that the capacitor to be measured will transfer a maximum charge to the integrator feedback capacitor. Additionally, the stray capacitance at the integrator input has little effect and the output will be a strong function of the value of the capacitor to be measured. The circuit has application in capacitor measurement and is useful as a ferroelectric memory preamplifier which acts to amplify the difference in capacitance produced by the polarization state of a ferroelectric memory capacitor. A CMOS preferred embodiment is disclosed in the form of a memory sense preamplifier.
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