VIPER28LD

Overview

The VIPER28LD is a high-voltage integrated circuit designed for low-power standby applications in AC-DC converters. It combines a high-voltage switched current source with a power MOSFET and advanced digital control logic on a single monolithic chip. The device features an internal 700V power switch, enabling operation from standard mains voltages without external high-voltage components. Key electrical parameters include a supply voltage range of 9V to 18V for the auxiliary winding, a peak drain current capability of 1.5A, and a switching frequency that varies between 40kHz and 60kHz depending on load conditions. The package type is DPAK (TO-252), providing robust thermal performance.

Feature Summary

• Integrated high-voltage startup current source eliminates external startup resistors
• Advanced digital control logic ensures stable operation across wide input voltage ranges
• Built-in thermal shutdown protection prevents damage during overheating events
• Frequency jittering reduces electromagnetic interference emissions

Applications

• Low-power AC-DC adapters for mobile phones and tablets
• Standby power supplies for consumer electronics
• Battery chargers for portable devices
• Auxiliary power supplies for home appliances

Procurement Notes

Verify the exact ordering code suffixes against the manufacturer's official datasheet to ensure correct packaging and temperature grade specifications. Confirm that the component matches the required pinout and thermal characteristics for your specific PCB layout design before finalizing procurement orders.

Selection Notes

Select this component when designing compact, cost-effective power supplies requiring minimal external components. Ensure the application demands low no-load power consumption and fits within the thermal constraints of the DPAK package. Validate that the input voltage range aligns with global mains standards.

Part Context

This part belongs to STMicroelectronics' VIPer family of high-voltage power switches. It is engineered for offline flyback converter topologies. The series emphasizes reliability and efficiency in small form-factor designs, targeting markets where space and energy efficiency are critical constraints.

Replacement Considerations

Check for direct pin-compatible alternatives such as the VIPER22 or VIPER12 series if different current ratings are needed. Verify functional equivalence regarding startup current and maximum duty cycle before substituting.