摘要 |
Transient offset error voltages due to charge injection by MOS analog switches and DC offsets of multipliers in switched-capacitor integrators of electronic metering circuits are compensated by the common mode rejection of a differential switched-capacitor integrator. To cancel internal DC offset voltages of the integrator amplifier, a series capacitor connected to the inverting input of the amplifier is charged, during the autozero phase of the clock cycle, to a voltage equal to the internal DC offset voltage of the amplifier and subsequently, during the integration phase of the clock cycle, this voltage is applied to the inverting input of the amplifier.
|