ADNS-2220 Avago Technologies US Inc., ADNS-2220 Datasheet - Page 30

• Manufacturer Part Number: ADNS-2220
• Description: SOLID STATE OPTICAL MOUSE LENS
• Manufacturer: Avago Technologies US Inc.

Specifications of ADNS-2220

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: Q2072083A

Shutter_Lower
Access: Read
Shutter_Upper
Access: Read
Data Type: Sixteen bit unsigned integer.
USAGE: Units are clock cycles. Read Shutter_Upper first, then Shutter_Lower. They should be read consecutively. The
shutter is adjusted to keep the average and maximum pixel values within normal operating ranges. The shutter value
is checked and automatically adjusted to a new value if needed on every frame when operating in default mode.
When the shutter adjusts, it changes by ± 1/16 of the current value. The shutter value can be set manually by setting
the AGC mode to Disable using the Extended_Config register and writing to the Shutter_Maximum_Bound registers.
Because the automatic frame rate feature is related to shutter value. It may also be appropriate to enable the Fixed
Frame Rate mode using the Extended_Config register.
Shown below is a graph of 250 sequentially acquired shutter values, while the sensor was moved slowly over white
paper.
Figure 28. Mean shutter vs. Z (white paper)
The maximum value of the shutter is dependent upon the setting in the Shutter_Max_Bound_
Upper and Shutter_Max_Bound_Lower registers.
30
Field
Field
120
100
Bit
Bit
80
60
40
20
0
-1.0
S
S
7
7
15
7
-0.8
-0.6
S
S
6
6
14
6
-0.4
Distance from Nominal Focus (mm)
Mean Shutter vs Z (White Paper)
S
S
5
5
13
5
Address: 0x0e
Reset Value: 0x85
Address: 0x0f
Reset Value: 0x00
-0.2
0.0
S
S
4
12
4
4
0.2
S
S
3
3
11
3
0.4
0.6
S
S
2
2
10
2
Avg
Avg - 3sigma
Avg + 3sigma
0.8
S
S
1
1
9
1
1.0
S
S
0
0
8
0