STMicroelectronics has introduced a primary-side switch IC for AC/DC converters. It is designed for use in DVD players, LCD monitors, set-top boxes, games consoles and other adaptors. It can also be used in stand-by power supplies for servers.
The VIPer53E can be used to build off-line power supplies with a secondary power capability of up to 30W with a wide input-voltage range, or 50W with a single European voltage range. It can sustain these ratings in a DIP-8 package without a heatsink. Its minimal stand-by consumption of 0.5W enables power supply makers to meet stringent ecological standards, such as those of the Blue Angel Eco and Energy Star programs.
The part combines an enhanced current-mode PWM controller with a high- voltage MDmesh power MOSFET, a start-up high-voltage current source and several on-chip protection circuits. The VIPer53E is an alternative to the VIPer53 for use when a power supply design only needs secondary regulation.
The VIPer53E can be used across a VDD range of 9 to 18V when used for secondary regulation, giving power supply designers greater flexibility in their choice of transformers.
The part has other benefits. Overload and short-circuit conditions are controlled by feedback monitoring and a delayed device reset. Its stand-by mode is made more efficient by enhancing the way the part skips pulses. The integrated startup current source is disabled during normal operation to reduce the input power required.
It offers other protections, against voltages of more than 18V and under- voltages, excessive temperatures and excessive drain currents. The switching frequency can be externally set at up to 300kHz.
The part is available in surface-mounting DIP-8 and PowerSO-10 packages. Pricing is US $0.90 in quantities of 10K pieces.
This press release is also available at: http://www.st.com/stonline/press/news/year2004/p1513c.htm … and includes links to further information on this product and ST’s complete range of VIPer products.