STMicroelectronics Enhances VIPer Family for Power Supplies

STMicroelectronics has introduced the VIPer17 off-line switched-mode converter, which integrates an 800V avalanche-rugged MOSFET as well as numerous features to save external components and ensure efficient operation during standby mode. Constant-current operation with an adjustable set point allows use with all mains voltages in SMPS (switched-mode power supply) designs up to 12W. The VIPer17 eliminates the need for external sensing components, as well as a startup resistor. Protection features include accurate, adjustable over-voltage and overload protection, hysteretic over-temperature protection, and two levels of over-current protection. Detection of a fault initiates the device’s auto-restart function, which prevents damage to the power supply or the load. An integrated soft-start function, active at startup or after a fault, reduces stress on the secondary diode and also helps prevent transformer saturation.



The VIPer17 automatically enters burst mode to maximize efficiency. The VIPer17 helps designers reduce system standby power and average power consumption to satisfy energy-saving initiatives such as Energy Star and Blue Angel. The device’s typical standby power consumption is 50mW, which can be reduced to 30mW when used in an optimized transformer design. Available variants are the VIPER17LN / VIPER17LD or VIPER17HN / VIPER17HD with fixed switching frequency of 60kHz or 115kHz, respectively. The new devices join ST’s existing VIPER12 and VIPER22 converters, and are available immediately for production orders, at $0.37 in quantities of 10,000 units.