SLVAEX3 October 2020 TPS8802 , TPS8804
One of the simplest methods of improving SNR is to take multiple ADC samples of the base pulse level. The improvement is demonstrated in Figure 4-20. Increasing the number of base ADC samples from 1 to 20 improves the SNR at 1 nA from 13.8 to 19.1 when one signal ADC sample is taken. When five signal ADC samples are taken, the SNR at 1 nA improves from 15.6 to 31.3. A small amount of power consumption is required to keep the photo amplifier enabled and take the extra ADC samples, but this amount is insignificant compared to the LED power consumption.
| tLED=100 μs | τ1=15 μs | τ2=15 μs |