EPR-18 Datasheet, PDF (22/28 Pages) Power Integrations, Inc. – Engineering Prototype Report for EP-18 10 W, Multiple Output, Isolated Power Supply with

10 W, Multiple Output, Isolated Power Supply
05-Dec-2002
12 Load Transient Response (75% to 100% Load Step)
Transient response is measured by changing the load, at twice the input line frequency,
from 75% and 100%. The peak of the output voltage response is controlled by the output
capacitor ESR while the recovery time is controlled by the output filter and the loop
response.
5V
3.3
0.5 A / div
5V
3.3
0.5 A / div
Figure 16 - 3.3 V and 5 VDC Response to 3.3 V
Load Step 75% - 100%
(1.125 A to 1.5 A) at 85 VAC
(5 V @ 0.9 A).
Figure 17 - 3.3 V and 5 VDC Response to 5 V
Load Step 75% - 100%
(0.9 A to 0.675 A) at 85 VAC
(3.3 V @ 1.5 A).
The stability of the power supply under various line and load conditions can be confirmed
by observing the phase margin at crossover (0 dB) and the attenuation (-dB) at positive
feedback (≥360^º Phase).
32dB Attenuation
72.8⁰ Phase margin
Figure 18 - Worst Case Phase Margin and Gain (Full Load VAC).
Power Integrations, Inc.
Tel: [phone] Fax: [phone]
www.powerint.com
Page 22 of 28