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AR0330CM
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38
Figure 37. Slave Mode Example with Equal Integration and Frame Readout Periods
(The integration of the last row is therefore started before the end of the programmed integration for the first row)
Inactive Active
Row 0
Row N
Inactive Active
Rising
Edge
Rising
Edge
Row Readout
Programmed Integration
Slave Mode
Trigger
Rising edge of VD
signal triggers the start
of the frame readout.
Row Reset
(start of integration)
Frame
Valid
VD Signal
Rising
Edge
The Slave Mode will become “Active” after the last row period.
Both the row reset and row read operations will wait until the rising edge of the VD signal.
Row reset and read
operations begin
after the rising edge
of the VD signal.
Integration due to
Slave Mode Delay
The row shutter and read operations will stop when the
slave mode becomes active and is waiting for the VD signal.
The following should be considered when configuring the
sensor to use the slave mode:
1. The frame period (T
FRAME
) should be configured
to be less than the period of the input VD signal.
The sensor will disregard the input VD signal if it
appears before the frame readout is finished.
2. If the sensor integration time is configured to be
less than the frame period, then the sensor will not
have reset all of the sensor rows before it begins
waiting for the input VD signal. This error can be
minimized by configuring the frame period to be
as close as possible to the desired frame rate
(period between VD signals).
Figure 38. Slave Mode Example where the Integration Period is Half of the Frame Readout Period
(The sensor read pointer will have paused at row 0 while the shutter pointer pauses at row N/2. The extra integration caused
by the slave mode delay will only be seen by rows 0 to N/2. The example below is for a frame readout period of 16.6ms while
the integration time is configured to 8.33 ms)
Inactive Active
Row0
Row N
Inactive Active
Rising
Edge
Rising
Edge
Slave Mode
Trigger
Frame
Valid
VD Signal
Rising
Edge
Reset operation is held during slave mode “Active” state.
Row reset and read
operations begin after
the rising edge of the
Vd signal.
8.33 ms
8.33 ms
Row Readout
Programmed Integration
Row Reset
(start of integration)
Integration due to
Slave Mode Delay