Overview
The VIPER27LDTR, produced by STMicroelectronics, is an off-line converter integrated circuit designed for high-performance applications. It features an 800 V rugged power section, PWM control, and multiple protection mechanisms including over-current, overvoltage, and hysteretic thermal shutdown. The device is optimized for low EMI through frequency jittering and includes a high voltage start-up circuit, soft-start, and safe auto-restart after fault conditions. It is particularly suited for applications requiring low standby power consumption and compliance with energy-saving regulations.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Drain-to-source (ground) voltage (VDRAIN) | 800 | V |
| Repetitive avalanche energy (EAV) | 5 | mJ |
| Repetitive avalanche current (IAR) | 1.5 | A |
| Pulse drain current (IDRAIN) | 3 | A |
| Operating frequency (VIPER27L) | 54-66 kHz | kHz |
| Operating frequency (VIPER27H) | 103-127 kHz | kHz |
| Standby power at 265 Vac | < 50 mW | mW |
| Drain-source on state resistance (RDS(on)) at 25°C | 7 Ω | Ω |
| Thermal shutdown temperature (TSD) | 150-160°C | °C |
| Thermal shutdown hysteresis (THYST) | 30°C | °C |
Key Features
- 800 V avalanche rugged power section
- PWM operation with frequency jittering for low EMI
- Operating frequencies: 60 kHz for L type and 115 kHz for H type
- Standby power < 50 mW at 265 Vac
- Limiting current with adjustable set point
- Adjustable and accurate overvoltage protection
- On-board soft-start
- Safe auto-restart after a fault condition
- Hysteretic thermal shutdown
- Brown-out protection with hysteresis
- Burst mode operation for high performance in standby mode
Applications
- Auxiliary power supply for consumer and home equipment
- ATX auxiliary power supply
- Low to medium power AC-DC adapters
- SMPS for set-top boxes, DVD players, and recorders
- SMPS for white goods
Q & A
- What is the maximum drain-to-source voltage of the VIPER27LDTR?
The maximum drain-to-source voltage is 800 V.
- What are the operating frequencies for the VIPER27L and VIPER27H types?
The VIPER27L operates at 60 kHz, and the VIPER27H operates at 115 kHz.
- What is the standby power consumption at 265 Vac?
The standby power consumption is less than 50 mW.
- Does the VIPER27LDTR have adjustable overvoltage protection?
- What is the purpose of the brown-out protection in the VIPER27LDTR?
The brown-out protection shuts down the device when the rectified input voltage level is below the normal minimum level specified for the system, and it restarts operation when the voltage exceeds the threshold.
- How does the VIPER27LDTR manage thermal protection?
The device features hysteretic thermal shutdown to protect against overheating.
- What is the role of the soft-start feature in the VIPER27LDTR?
The soft-start feature ensures a gradual increase in the output voltage during power-up to prevent inrush currents.
- Can the current limit set point be adjusted in the VIPER27LDTR?
- What is the purpose of the burst mode operation in the VIPER27LDTR?
The burst mode operation helps in achieving high performance in standby mode and aids in meeting energy-saving regulations.
- What types of packages are available for the VIPER27LDTR?
The VIPER27LDTR is available in DIP-7, SO16 narrow, and tape and reel packages.
