Use
This feature can beuseful in case the resonant tank is not able to regulate the output at light/no loads even at the
minimum time shift value. If the time shift has reached its minimum value, the feature allows entering the burst
mode if the condition is asserted for at least 480 μs,in addition to the “Burst entering digital filtering”. This will
prevent output overshoot. For this reason, the feature will not wait for the “No-burst window width” time before
entering burst mode.
3.5.3
Burst entering digital filtering
Size:2 bits
Sets the digital filtering to enter the burst mode. Available values are:
•
270 μs
•
510 μs
•
750 μs
•
990 μs
To enter burst mode, the burst request (external or LLC_FB pin driven) must be asserted for the time defined by
this parameter.
This allows reject noise on LLC_FB and LLC_AUX pins.
3.5.4
LLC_FB burst entering thr
Size:6 bits
Sets the voltage threshold to enter the burst mode.
Available values are:
Voltage on LLC_FB pin
•
268.6 mV
•
278.3 mV
•
288.1 mV
•
297.9 mV
•
307.6 mV
•
317.4 mV
•
327.1 mV
•
336.9 mV
•
346.7 mV
•
356.4 mV
•
366.2 mV
•
376.0 mV
•
385.7 mV
•
395.5 mV
•
405.3 mV
•
415.0 mV
•
424.8 mV
•
434.6 mV
•
444.3 mV
•
454.1 mV
•
463.9 mV
•
473.6 mV
•
483.4 mV
•
493.2 mV
•
502.9 mV
•
512.7 mV
•
522.5 mV
•
532.2 mV
•
542.0 mV
•
551.8 mV
Equivalent time shift
•
350 ns
•
383.3 ns
•
416.7 ns
•
450 ns
•
483.3 ns
•
516.7 ns
•
550 ns
•
583.3 ns
•
616.7 ns
•
650 ns
•
683.3 ns
•
716.7 ns
•
750 ns
•
783.3 ns
•
816.7 ns
•
850 ns
•
883.3 ns
•
916.7 ns
•
950 ns
•
983.3 ns
•
1017 ns
•
1050 ns
•
1083 ns
•
1117 ns
•
1150 ns
•
1183 ns
•
1217 ns
•
1250 ns
•
1283 ns
•
1317 ns
UM3002
Burst mode parameters
UM3002
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Rev 1
page 27/42