ADuM1410/ADuM1411/ADuM1412
The insulation lifetime of the ADuM141x depends on the
voltage waveform type imposed across the isolation barrier. The
iCoupler insulation structure degrades at different rates
depending on whether the waveform is bipolar ac, unipolar ac,
or dc. Figure 20, Figure 21, and Figure 22 illustrate these
different isolation voltage waveforms.
Note that the voltage presented in Figure 21 is shown as
sinusoidal for illustration purposes only. It is meant to represent
any voltage waveform varying between 0 V and some limiting
value. The limiting value can be positive or negative, but the
voltage cannot cross 0 V.
Bipolar ac voltage is the most stringent environment. The goal
of a 50-year operating lifetime under the ac bipolar condition
determines the Analog Devices recommended maximum
working voltage.
RATED PEAK VOLTAGE
0V
Figure 20. Bipolar AC Waveform
In the case of unipolar ac or dc voltage, the stress on the
insulation is significantly lower. This allows operation at higher
working voltages while still achieving a 50-year service life. The
working voltages listed in Table 10 can be applied while
maintaining the 50-year minimum lifetime provided the voltage
conforms to either the unipolar ac or dc voltage case. Any cross-
insulation voltage waveform that does not conform to Figure 21
or Figure 22 should be treated as a bipolar ac waveform, and its
peak voltage should be limited to the 50-year lifetime voltage
value listed in Table 10.
RATED PEAK VOLTAGE
0V
Figure 21. Unipolar AC Waveform
RATED PEAK VOLTAGE
0V
Figure 22. DC Waveform
Rev. H | Page 21 of 24
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