Patent Number: 6,166,766

Title: Sensing circuit for capturing a pixel signal

Abstract: A sensing circuit (202) uses correlated double sampling to sample a first pixel signal of a pixel stream (V.sub.PIXEL) at two different times to produce a dark signal and a light signal on two capacitors (310, 314). The dark and light signals are amplified in an amplifier (302) to produce a differential output signal (V.sub.PP -V.sub.PN) proportional to their difference. While the samples of the first pixel signal are being amplified, a second pixel signal is double-sampled to produce dark and light signals on two other capacitors (312, 316) for amplifying in the same amplifier. The period of the pixel signal is divided into time slots (T.sub.1 -T.sub.16) by a clocked oscillator (52). Programming signals (PROG1, PROG2) control the time slots in which sampling control pulses (V.sub.S1, V.sub.S2) are generated.

Inventors: Moore; Kendall G. (Tempe, AZ), Shapiro; Frederic B. (Phoenix, AZ), Beckwith; Deborah J. (Chandler, AZ), Hodel; Michael W. (Mesa, AZ)

Assignee: Motorola, Inc.

International Classification: H04N 5/217 (20060101); H04N 005/217 ()

Expiration Date: 12/26/2017