AN1344 Datasheet, PDF (11/14 Pages) STMicroelectronics – The VIPer100A-E is designed to deliver

AN1344
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Thermal consideration
Thermal consideration
Temperature measurement was taken at room ambient of 24 °C, convection air-cooled
resulted in the VIPer100A-E tab temperature of 91.1 °C at 115 V_ac input with a 6 A output.
Results may vary depending on final application.
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Overcurrent limiting
This power supply was designed for an audio application where music peaks can exceed
the maximum current of the power supply. In a sound entertainment system it is imperative
for the power supply to not shut down during such peaks. It is acceptable for the voltage to
decrease as the current increases. This maintains constant power for the unit. Under a short
circuit condition, this unit cycles on and off or "hiccup mode". In Figure 8 the output voltage
versus the output current is shown. Maximum output power reached is 163 W. The
VIPer100A-E also has thermal shutdown with hysteresis that is located close to the Power
MOSFET portion of the die, which protects it from exceeding the temperature limit of the I.C.
Figure 8. Output voltage versus the output Figure 9. Transient Response 50% step
current
change
Figure 10. Output Ripple
Figure 11. EMI measurement
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