MT9V032
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34
ON−CHIP BIASES
ADC Voltage Reference
The ADC voltage reference is programmed through
R0x2C, bits 2:0. The ADC reference ranges from 1.0V to
2.1V. The default value is 1.4V. The increment size of the
voltage reference is 0.1V from 1.0V to 1.6V (R0x2C[2:0]
values 0 to 6). At R0x2C[2:0] = 7, the reference voltage
jumps to 2.1V.
The effect of the ADC calibration does not scale with
V
REF. Instead it is a fixed value relative to the output of the
analog gain stage. At default, one LSB of calibration equals
two LSB in output data (1LSB
Offset
= 2mV, 1LSB
ADC
=
1mV).
It is very important to preserve the correct values of the
other bits in R0x2C. The default register setting is 0x0004.
V_Step Voltage Reference
This voltage is used for pixel high dynamic range
operations, programmable from R0x31 through R0x34.
Chip Version
Chip version registers R0x00 and R0xFF are read−only.
