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So if we check the figure and the sensitivity the change in wavelength changes the sensitivity response. The change in Lux also changes the current by 1.2. Typically, the white light is used as the source which consists of 3Volts input signal with 100 illuminance. However the output depends on the load ressistor connected with the sensor. 

Interface Electronic circuits

The APDS-9003 is an anlog-output ambient light photo sensor. This photo sensor produces a high gain photo current that can be converted to voltage with a standard value of external resistor. Thus the higher we need the output of the sensor, a higher value resistor can be used to apply it in our electronic circuits with ADC input. Thus with the resistor fixed, the voltage output is dependent on the photo current which is generated by the brightness of the light stone on the photo sensor. Hence increase in the brightness of light and load resistor will increase the output voltage. Hence, We must be sensible in selecting the load resistor in order to determine the amount of current voltage conversion in the circuit.

Inorder to get a typical output voltage of 2.32V, We need to have the 3V input voltage for this sensor. As all the electronic devices, this light sensor also consists of noise to external excess light.

Light sources consists of ac noise frequencies. For example a flourescent light consists of about 100Hz ac noise frequency. A low pass filter is required to be added in the circuit parallel with the load resistor to decrease the ripple.

Image AddedFigure 3: Electronic configuration for APDS-9003

As shown in figure 3, The 3V Vcc is supplied to the sensor in pin 1 and pins 2 to 5 are not connected. Pin 6 is the output pin. When a light source strikes the sensor it produces photo current. The current through load resistor creates the analog voltage output. The capacitor in parallel with the RL filters the noise and the filtered signal is converted to digital format in our electronic devices using A/D converter or a microcontroller.

References

  1. APDS-9003, Avago Technologies datasheet
    URL: http://www.avagotech.com/docs/AV01-0238EN [Online], Last Accessed: 10.4.2014