MT9M034

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12

Table 6. FRAME TIME: LONG INTEGRATION TIME

Parameters

Name

Equation (Number of Pixel Clock Cycles)

Default Timing

at 74.25 MHz

F’

Total Frame Time

(Long Integration Time)

Context A: (R0x3012 x (A + Q)) + R0x3014 + P1 + P2

Context B: (R0x3016 x (A + Q)) + V R0x3018 + P1 + P2

3,300,012 pixel

clocks

= 44.44 ms

1. The MT9M034 uses column parallel analog−digital converters; thus short line timing is not possible. The minimum total line time is 1650

columns (horizontal width + horizontal blanking) for HDR mode and 1400 for linear mode. The minimum horizontal blanking is 370.

Exposure

Total

integration

time

is

the

result

of

Coarse_Integration_Time

and

Fine_Integration_Time

registers, and depends also on whether manual or automatic

exposure is selected.

(eq. 2)

= (number of lines of integration x line time) − (410 pixel

clocks of conversion time overhead) − (number of pixels of

integration x pixel time)

where:

Control: Enabled)

When automatic exposure control (AEC) is enabled,

the number of lines of integration may vary from

frame to frame, with the limits controlled by

R0x311E (minimum auto exposure time) and

R0x311C (maximum auto exposure time)

Control: Disabled)

If AEC is disabled, the number of lines of

integration equals the value in R0x3012 (context A)

or R0x3016 (context B)

The number of fine shutter width pixels is

independent of AEC mode (enabled or disabled):

equals the value in R0x3014

equals the value in R0x3018. Maximum value for

Typically, the value of the Coarse_Integration_Time

register is limited to the number of lines per frame (which

includes vertical blanking lines), such that the frame rate is

not affected by the integration time. For more information

on coarse and fine integration time settings limits, please

refer to the Register Reference document.

NOTE: In HDR mode, there are specific limitations on

coarse_integration_time due to the number of

line buffers available. Please refer to the section

called “HDR Specific Exposure Settings”.

For best image quality, it is recommended that the

integration time be set to two rows or greater for the shortest

exposure, particularly for monochrome sensors. For linear

mode, this would be the coarse integration time (R0x3012).

For HDR mode, the integration time should be set such that

the T3 exposure is 2 rows or greater. Setting the exposure

time to 1 row may result in non−uniformity between rows.