PI3042A Datasheet, PDF (6/18 Pages) AMI SEMICONDUCTOR – Contact Image Sensor Chip

Preliminary PI3042A datasheet
TP
FROM
IOUT
PAD
CAP
OP-AMP
VIDEO OUT
SW
RIN
RFB
Figure 5. Video Output Circuit & Application Circuit
Since switching energies are high frequencies components, they tend to integrate to a 0 value and the
remainder adds a constant value to off-set the dark level. After the pixel is integrated, the CAP is reset
to zero volts by activating the shunt switch, SW, that connects the video line to ground prior to
accessing the following pixel element. As it is seen, depicting a typical pixel voltage waveform, in
Figure 6, Single Pixel Output Voltage, the shunt time is controlled with CP. Simultaneous to SW
activation, the pixel element storage is, also, reset to the dark reference level, hence initializing the
pixel for its integration process cycle. The signal pixels Vp(n) is referenced to its Dark Level as it is
seen in Figure 6.
Figure 6. Single Pixel Video Output
Two Test Setups For Specifications And Performance
First Setup: The standard specifications are the image sensor tests that are performed on the wafer
probe machine where each device on the wafer are tested in production. However, the data in these
measurements are measured with a clock frequency at a fixed 500 KHz. Since the pixel rate is equal
to the clock rate, the pixel rate is also at 500KHz. The specification under the section Electro-Optical
Characteristics (25^o C) is the wafer probe specifications, Table 2.
Page 6 of 18 Date: 09/23/05