
MOTOROLA
Revision 8.0 - 28 November 2001 : MCM20027
14
MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
ImageMOS
6.3 SFRS Frame Time/Rate:
In Single Frame Rolling Shutter capture mode the Frame
time is defined as:
Frame time = T
frame
= Integration time+Readout time
Readout time is the amount of time to readout the data af-
ter integration of the row has been completed. It is defined
as follows:
Readout time = (vrd
d
+ 1) * T
row
where
vrd
d
defines the number of rows in the virtual
frame. The user controls vrd
d
via the CFRS Virtual Frame
Row Depth registers (
Table 42 on page 55
and
Table 43
on page 55
).
T
row
= (vcw
d
+ shs
d
+ shr
d
+ 19) * MCLK
period
For
Integration time
see
“Integration Time in SFRS
mode” on page 14
6.3.1 Integration Time in SFRS mode
The Integration time in Single Frame Rolling Shutter cap-
ture mode is the same as in Rolling Shutter Capture
Mode. For further information, see
“Integration Time in
CFRS mode:” on page 13
. T
he only difference is that
in this mode the Integration time is NOT bounded by
the Frame time
6.4 Example of Frame time/rate and Integration Time
in CFRS and SFRS modes
The following illustrates how to determine the Frame time/
rate and Integration time in both capture modes:
Assumptions:
1) Active Window of Interest = 1280 x 1024
i.e..
(wcw
d
)=1279
(
wrd
d
)=1023
2) Virtual Column Width (
vcw
d
)= 1290
3) Virtual Row Depth (
vrd
d
) = 1034
4) Sample & hold time (
shs
d
) = 10
5) Sample & hold time (
shr
d
) = 10
6) Integration Time (
cint
d
)= 350
7) MCLK = 13.5 Mhz
NOTE!!
vcw
d
and
cint
d
are typically varied frame to
frame
Calculations:
Row Time =Trow = (vcwd + shsd + shrd + 19)
= (1290 + 10 + 10 + 19) / 13.5e6
= 98.44
μ
s
Integration Time = (cintd + 1) * Trow
=(350+1)*98.44
μ
s
=34.5ms
Readout time = (vrdd + 1) * Trow
= Frame time in CFRS mode
Frame Time in CFRS mode = (vrd
d
+ 1) * Trow
T
frame
=(1034 + 1)* 98.44
= 101.34 ms
Frame Time in SFRS mode =
T
frame
= Integration time+Readout time
= 34.5ms + 101.34ms
= 135.84ms
Results
NOTE!! CFRS Integration time = 34.5ms because:
T
int
<
T
frame
= (vrd
d
+ 1) * T
row
(see
“Integration Time in CFRS mode:” on page 13
)
Capture Mode
T
int
T
frame
CFRS
34.5ms
101.34 ms
SFRS
34.5ms
135.84ms