EPR-29 – 4 Output, 11 W, Universal Input, DVD Supply
07-July-03
11.4 Load Transient Response (75% to 100% Load Step)
In the figures shown below, signal averaging was used to better enable viewing the load
transient response. The oscilloscope was triggered using the load current step as a
trigger source. Since the output switching and line frequency occur essentially at random
with respect to the load transient, contributions to the output ripple from these sources
will average out, leaving the contribution only from the load step response.
11.4.1 Transient Response for 3.3 V and 5 V Outputs
Figure 24 – Transient Response, 115 VAC,
75-100-75% Load step on 5 V
Upper: 5 V Load Current, 0.5 A / div.
Middle: 3.3 V output, 50 mV / div.
Lower: 5 V output, 50 mV / div.
All 500 µs / div.
Figure 25 – Transient Response, 230 VAC,
75-100-75% Load step on 5 V
Upper: 5 V Load Current, 0.5 A / div.
Middle: 3.3 V output, 50 mV / div.
Lower: 5 V output, 50 mV / div.
All 500 µs / div.
Power Integrations, Inc.
Tel: +1 408 414 9200 Fax: +1 408 414 9201
www.powerint.com
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