Quantifi Photonics BERT 1005 Series, Руководство пользователя

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Bit Error Rate Tester | BERT 1005
Quantifi Photonics Ltd. Version 2.04 54
8.5.1.3 Set the amplitude
The amplitude of the output voltage can be set for each PPG channel. The value must be within the valid
range of 200 mV to 1100 mV.
To set the amplitude for a channel, type an appropriate value in the AMPLITUDE field. The value can also
be set to the MIN and MAX value by clicking the dropdown lists in the AMPLITUDE field, or by clicking the
up and down arrows to increase or decrease the value.
8.5.2 Set the cross-point level
The pattern generator has a cross-point adjust function to set the output waveform crossing point as
shown below. The output crossing point range is programmable from 35% to 55%.
𝐶𝑃𝐴 = (
𝑌 − 𝐴𝑣𝑒𝑟𝑎𝑔𝑒 0
𝑋 − 𝐴𝑣𝑒𝑟𝑎𝑔𝑒 0
) × 100
The crossing point percentage represents the amplitude of the crossing point relative to the distance
between the Average zero (0) and one (1) levels. For this measurement, the average zero and one level
amplitudes are measured at the center of the eye, within the middle 20% of the bit period. The crossing
point amplitude is measured relative to the Average 0 level. The crossing point percentage is calculated
as the crossing point amplitude (Y) divided by the distance between the average zero and one levels (X).
To the set the cross-point level for a channel, select an appropriate value from the CROSS POINT drop-
down list.