TH7804A Datasheet, PDF (7/11 Pages) ATMEL Corporation – Linear Charged Couple Device (CCD) Image Sensor 1024 Pixels

Figure 4. CTF Typical Curves (2854 K Source)
TH7804A
Electro-optical Performance Without Infrared Cut-off Filtering
The TH7804A’s special semiconductor process enables it to exploit the silicon's high
near infrared sensitivity while maintaining good imaging performance in terms of
response uniformity and resolution. Typical changes in performance with and without IR
filtering are summarized below.
Average Video Signal Due to a Given Scene Illumination
PRNU (Single Defects Excluded)
CTF at Nyquist Frequency
With IR Cut-off Filter
V_OS
±5%
70%
No IR Cut-off Filter
V_OS x 4
±5%
50%
Complementary
Operating Modes
TH7804A may be used in several configurations in regards to video output sampling and
charge sensing reset.
1. Sampling Options:
Inhibition of internal sampling pulses allows for two possibilities:
a. no sampling: video output delivered in unsampled form,
b. sampling by external clocks: external sampling pulses directly applied to
Φ_ECHA, Φ_ECHB inputs.
If internal sampling clocks SΦ_ECHA and SΦ_ECHB are not used, it is recommended of
unpower the corresponding clock drivers, as this will greatly reduce on-chip power
consumption.
2. External Reset Option:
The position and period of the charge reset clocks may be optimized by using external
clocks on Φ_RA and Φ_RB inputs. This is specially interesting to optimize the video outputs
for Correlated Double Sampling (in order to reduce noise and improve S/N ratio).
Control signals to be applied in the different configurations are shown in Table 6.
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