SFH 5712-2/3 OSRAM Opto Semiconductors Inc, SFH 5712-2/3 Datasheet - Page 10

• Manufacturer Part Number: SFH 5712-2/3
• Description: LIGHT SENSOR AMBIENT SMD
• Manufacturer: OSRAM Opto Semiconductors Inc

Specifications of SFH 5712-2/3

• Package / Case: 4-SMD, No Leads
• Wavelength: 500nm
• Output Type: I²C™
• Operating Supply Voltage: 2.5 V
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: - 15 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 475-2913-2; Q65110A8485

Appendix 1: Flicker reduction and timing
Sensor is smoothing the output signal by averaging up to 32 single measurements. Flicker caused by
artificial light sources e.g. from fluorescent lamps usually occurs at 100Hz or 120Hz. Oscillation of the
optical input signal will be reduced by 13dB at the output for sinus signals. E.g. the sensor output varation
will only be 5% of the optical input peak to peak variation from fluorescent light. The flicker reduction is
calculated by the relative variation of the optical input signal (a/A) compared to the sensor output (b/B),
see figure 2.
To achieve the maximum flicker reduction performance the 32fold averaged output value should be
used. Typically 186ms (max. 250ms) after sensor activation the first full averaged signal can be read at
the sensor output. The sensor allows to read intermediate signal output values prior to 250ms (see
figure 3):
- single measurement after typ. 1ms
- average of 8 measurements after typ 45ms
- average of 16 measurements after typ 92ms
After the first full averaged measurement value (t>250ms) the output will be refreshed automatically
twice a second with 32fold averaged values. Single, 8 and 16fold averaged measurements are only
performed after activation of the sensor.
2010-03-31
Figure 2 flicker reduction (average of 32 measurements)
Average signal level of
optical input (A) and
SFH 5712 out (B)
10log [(b/B) / (a/A)]
a
10
Actual light level
b
SFH 5712 Out
OHF04362
SFH 5712
Time