ISL29038 Datasheet, PDF (7/15 Pages) Xicor Inc. – Low Power Ambient Light and Proximity Sensor with Enhanced Infrared Rejection

ISL29038
Typical Performance Curves
100
90
80
250mA
70
60
125mA
50
62.5mA
40
30
31.25mA
20
10
0
0
20
40
60
80
18% GREY CARD PROXIMITY DISTANCE (mm)
FIGURE 6. PROXIMITY SENSITIVITY (Note 12)
100
90
80
70
60
50
40
30
20
10
0
300
ALS RESPONSE (BLUE)
RANGE: 2k Lux
CIE 1924 PHOTOPIC CURVE
400 500 600 700 800 900
WAVELENGTH (nm)
FIGURE 7. ALS SENSITIVITY (Note 13)
1000 1100
15
100
90
80
70
10
60
50%
50
40
5
30
20
10%
10
0
0
8k
16k
24k
32k
40k
AMBIENT LIGHT LEVEL (LUX)
FIGURE 8. PROXIMITY AMBIENT LIGHT REJECTION (Note 14)
0
-90
-60
-30
0
30
ANGLE (°)
60
90
FIGURE 9. ALS ANGULAR SENSITIVITY (Note 15)
NOTES:
12. Figure 6 shows ISL29038 Proximity distance sweeps with different IRDR LED current settings using an 18% Grey card reflector.
13. Figure 7 shows ISL29038 Ambient Light Sensor Spectral response when compared to a theoretical CIE 1924 Photopic curve. The ‘Blue’ line shows
the ISL29038 response and the ‘Red’ line depicts the CIE 1924 Photopic curve.
14. Figure 8 shows the ISL29038 Proximity Ambient Light Rejection using a Norwood Solar Emulator. At 40k lux ambient light level, the Proximity
Washout Count (Reg 0x0D[7:1]) is 127 indicating a saturation in Proximity Signal processing path. The Proximity Washout bit 0x0D[0] is active at
approximately 90% of the maximum level. At 10% initial PROX count (due to optical leakage from IR LED to the ISL29038), the PROX data error is
under 2%. At 50% initial PROX count (severe optical leakage), the PROX data error is about 7%.
15. Figure 9 shows the Ambient Light Sensor Angular Sensitivity of the ISL29038 using a white LED light source.
7
FN7851.0
October 12, 2012