LCS700-708
PI-6470-062811
Higher fSTART will decrease the load threshold at which bursting
begins, increase the input voltage threshold and decrease the
output ripple in burst mode, but will increase the burst repetition
rate, which may introduce audible noise in some combinations
of line and load. The choice of fSTART will affect the large signal
transient response where the HiperLCS goes in and out of burst
mode.
24.1
24.0
23.9
400
300
200
100
0
-5
50
Time (μs)
100
0
Figure 26. Zoom in of Last Few Switching Cycles of Burst Pulse Train of Figure 24.
The Switching Frequency of the Last Few Cycles is fSTOP, 383 kHz in
This Case (arrow). The Ringing in VHB After Switching Stops, is the
Primary Inductance Ringing with the MOSFET Capacitance.
18
Rev. B 062011
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