EPR-00011 - 70 W Adapter 22-Jan-01
Page 26 of 46
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10.3 Output Voltage During Power-down
Both waveforms were captured using a Yokogawa Oscilloscope. Upper trace is V
OUT,
the
output voltage and the lower trace is V
C7
, the voltage across the input capacitor (C7).
Timebase is 50 ms/div.
During power down the output voltage falls to zero with no ‘glitching’ due to line under
voltage sensing.
Figure 20 - Shut-down, 5.25 Ω load, 85 V
AC
V
OUT
& V
C7
(10 & 100V/div,50ms/div)
Figure 21 - Shut-down, No-load, 85 V
AC
V
OUT
& V
C7
(10 & 100V/div,50ms/div)
10.4 Drain Voltage and Current during Power-Up (265 V
AC
)
The waveform was captured using a Yokogawa oscilloscope.
Figure 22 – Start-up, 5.25 Ω load, 265 V
AC
V
DRAIN
& I
DRAIN
(200 V & 1 A/div, 1µs/div)
Peak DRAIN voltage is acceptable at < 600 V, well below the recommended maximum of
650 Vpk. DRAIN current waveform shows no sign of core saturation.
V
OUT
V
C7
V
DRAIN
I
DRAIN
