AN1094 Datasheet, PDF (1/9 Pages) STMicroelectronics – Solution for off-line SMPS using VIPer100-E

AN1094
Application note
Solution for off-line SMPS using VIPer100-E
Introduction
The present board prototype is a wide-range input off-line 50 W single switch Flyback,
working at 100 kHz. It is based on a new off-line smart switcher: the VIPer100-E.
The VIPer100-E is a current mode PWM with a 620 V / 2.5 Ω power switch, able to
withstand an avalanche current during normal operation. The start-up of the circuit is done
with an internal high voltage current source, which is switched off during steady state. It also
includes a regulation function designed to minimize the pin count, while maintaining design
flexibility. Figure 2 presents the internal block diagram of this monolithic device. Such a
device can be easily used in any off-line flyback SMPS, with a 100 W power capability for a
single input voltage range, or 50 W with a wide input range. This stand-alone off-line Smart
Switcher concept provides a cost effective solution for SMPS for many applications such as
VCRs, TV sets, satellite receivers or decoders. The benefits for the customer are a simpler
design phase and a reduced overall components count due to the optimization of the
product configuration.
Figure 1. Standard evaluation board VIPerKITBD
October 2007
Rev 2
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