ADNS-5050 Avago Technologies US Inc., ADNS-5050 Datasheet - Page 19

• Manufacturer Part Number: ADNS-5050
• Description: 8 DIP SFF Navigation Sensor
• Manufacturer: Avago Technologies US Inc.

Specifications of ADNS-5050

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 516-2261; ADNS-5050

SQUAL
Access: Read
Data Type:
USAGE:
Figure 13. Squal values (white paper).
Figure 14. Mean squal vs. Z (white paper).
19
60
50
40
30
20
10
0
60
50
40
30
20
10
0
1
55
1.6
109 163 217 271 325 379 433 487 541 595 649 703 757 811 865
Bit
Field
Upper 8 bits of a 9-bit unsigned integer.
SQUAL (Surface Quality) is a measure of the number of valid features visible by the sensor in the current
frame. The maximum SQUAL register value is 128. Since small changes in the current frame can result in
changes in SQUAL, variations in SQUAL when looking at a surface are expected. The graph below shows
few sequentially acquired SQUAL values, while a sensor was moved slowly over white paper. SQUAL
is nearly equal to zero, if there is no surface below the sensor. SQUAL is typically maximized when the
navigation surface is at the optimum distance from the imaging lens (the nominal Z-height).
Delta from Lens Reference Plane to Tracking Surface, Z (mm)
1.8
7
SQ
Address: 0x05
Reset Value: 0x00
2
7
2.2
6
SQ
6
2.4
Count
2.6
5
SQ
5
2.8
4
SQ
4
3
3.2
3
SQ
3
3.4
2
SQ
2
1
SQ
Avg-3sigma
Avg
Avg+3sigma
1
0
SQ
0