×

Charge-domain analog readout for an image sensor

  • US 6,222,175 B1
  • Filed: 03/08/1999
  • Issued: 04/24/2001
  • Est. Priority Date: 03/10/1998
  • Status: Expired due to Term
First Claim
Patent Images

1. A charge-domain readout circuit comprising:

  • a plurality of column readout circuits each of which can sample and store signal and reset values of an active pixel sensor, wherein each of the column readout circuits is associated with a respective column of sensors in an active pixel sensor array;

    a first bus for receiving the signal value stored by a selected one of the column readout circuits;

    a second bus for receiving a reset value stored by the selected one of the column readout circuits; and

    an operational amplifier-based charge sensing circuit, wherein the charge sensing circuit maintains a substantially constant voltage on the first and second buses and wherein the charge sensing circuit provides a differential output based on the values stored by the selected one of the column readout circuits.

View all claims
  • 4 Assignments
Timeline View
Assignment View
    ×
    ×