LM9823CCWM NSC [National Semiconductor], LM9823CCWM Datasheet - Page 15

• Manufacturer Part Number: LM9823CCWM
• Description: LM9823 3 Channel 48-Bit Color Scanner Analog Front End
• Manufacturer: NSC [National Semiconductor]

Table 2: Configuration Register Parameters
Note: Power-Up Default Register Settings are shown in Bold Italics
Typical Gain Values
Boost Gain Enable
PGA Gain Value
Offset Polarity
Typical Offset
Offset Value
Parameter
(Address)
Values
Gain
B4(MSB)
B4(MSB)
(SIGN)
(x3)
• • •
• • •
• • •
• • •
• • •
B5
B5
B5
B5
0
1
0
0
0
0
0
1
1
1
1
1
0
1
0
0
0
0
0
0
1
1
1
1
1
1
Red, Green and Blue Offset DAC Settings (1, 2 & 3)
(MSB)
(MSB)
Red, Green and Blue Gain Settings (4, 5 & 6)
• • •
• • •
• • •
• • •
• • •
B3
B4
B3
B4
0
0
0
1
1
0
0
0
1
1
0
0
0
1
1
1
0
0
0
1
1
1
• • •
• • •
• • •
• • •
• • •
B2
B3
B2
B3
Control Bits
0
0
0
1
1
0
0
0
1
1
0
0
0
1
1
1
0
0
0
1
1
1
• • •
• • •
• • •
• • •
• • •
B1
B2
B1
B2
0
0
0
1
1
0
0
0
1
1
0
0
0
1
1
1
0
0
0
1
1
1
Gain = Boost Gain * PGA Gain
15
B0(LSB)
B0(LSB)
• • •
• • •
• • •
• • •
• • •
B1
B1
0
0
1
1
1
0
0
1
1
1
0
0
1
0
1
1
0
0
1
0
1
1
(Continued)
Boost Gain = 1V/V
Boost Gain = 3V/V
Negative Offset
Positive Offset
Typical Offset = 20LSBs * Offset Value * PGA Gain
PGA Gain (V/V) =.933 + 0.0667 * (PGA Gain Value)
(LSB)
(LSB)
• • •
• • •
• • •
• • •
• • •
B0
B0
0
1
0
0
1
0
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Typical Offset (with PGA Gain = 1)
Typical Gain
12 bit LSBs
Result
+600
+620
(V/V)
0.00
-600
-620
0.93
1.00
1.07
2.87
2.93
3.00
2.79
3.00
3.20
8.60
8.80
9.00
+20
+40
• • •
• • •
• • •
• • •
• • •
-20
-40
0
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