## VIPER013LS: Electronic Characteristics and Overview The **VIPER013LS** is a high-voltage converter belonging to the VIPerPlus family by STMicroelectronics. It is designed specifically for high-performance offline power supplies, integrating an 800 V avalanche-rugged power MOSFET with a Pulse Width Modulation (PWM) controller. --- ### 1. Key Technical Specifications The following table summarizes the primary electrical parameters of the VIPER013LS: | Parameter | Specification | | :--- | :--- | | **Drain-Source Voltage ($V_{DSS}$)** | 800 V | | **Switching Frequency ($F_{OSC}$)** | 60 kHz | | **Max Drain Current ($I_{D}$)** | 360 mA (Typical peak) | | **Supply Voltage Range ($V_{CC}$)** | 4.5 V to 30 V | | **Output Power Capability** | ~7W (Wide range) / ~10W (European range) | | **Package Type** | SSOP10 | --- ### 2. Core Internal Components The VIPER013LS integrates several critical electronic sections into a single chip to reduce BoM (Bill of Materials) costs: 1. **Power MOSFET:** An 800 V rated MOSFET that allows the device to withstand high voltage spikes without requiring complex snubber circuits in low-power applications. 2. **PWM Controller:** Manages the switching logic. It uses current-mode control with adjustable current limits. 3. **High-Voltage Startup:** Includes an internal high-voltage current source that charges the $V_{CC}$ capacitor during startup, eliminating the need for external startup resistors. 4. **Error Amplifier:** Features an embedded transconductance error amplifier with a 1.2 V reference voltage. --- ### 3. Integrated Protections The device is "smart" because it includes several autonomous safety features: * **Pulse-Skip Mode:** Activates during extremely light loads to minimize power consumption (supporting "Green" energy standards). * **Hiccup Mode:** Triggered during short-circuit or overload conditions to prevent thermal runaway. * **Thermal Shutdown:** The chip turns off if the internal junction temperature exceeds approximately 150°C. * **Frequency Jittering:** Slightly modulates the switching frequency to reduce EMI (Electromagnetic Interference) emissions. --- ### 4. Basic Application Circuit Logic In a typical Buck or Flyback converter setup, the VIPER013LS operates as follows: ```text [Line Input] -> [Bridge Rectifier] -> [Bulk Cap] -> [VIPER013LS Drain] | [PWM Control] -> [Source/GND] | [Feedback Loop] <--------------------------+ ``` 1. **Drain Pin:** Connected to the primary side of the transformer or inductor. 2. **FB (Feedback) Pin:** Receives the signal from the optocoupler or direct voltage divider to regulate output. 3. **VCC Pin:** Supplies power to the internal logic; usually bypassed with a small ceramic capacitor.