STMicroelectronics VIPER06XN

Overview

VIPER06XN from STMicroelectronics is a high-voltage offline PWM controller with integrated 800 V avalanche-rugged N-channel power MOSFET, operating at fixed 30 kHz switching frequency with ±2 kHz jitter modulation. It delivers up to 6 W in enclosed adapters and supports direct mains-powered flyback/buck topologies without auxiliary winding. Designed for energy-efficient low-power AC/DC conversion, it enables <30 mW standby power at 265 VAC in home appliance and LED driver applications.

For engineers reviewing the VIPER06XN datasheet, VIPER06XN pinout, VIPER06XN application, or VIPER06XN equivalent, key selection criteria include its self-biasing capability, adjustable current limit via LIM pin, burst-mode operation below VCOMPL (1.1 V), and thermal shutdown at 155 °C - all critical for meeting IEC 62368-1 and Energy Star Level VI requirements in compact, cost-sensitive power supplies.

Technical Context

The VIPER06XN integrates a SenseFET-based current-sensing architecture and a hysteretic thermal shutdown circuit with 30 °C hysteresis, enabling robust overtemperature recovery without external components. Its oscillator employs fixed-frequency spread-spectrum modulation at 230 Hz to reduce EMI peak emissions by distributing harmonic energy across sidebands.

Control logic combines cycle-by-cycle current-mode PWM with open-loop failure detection: when FB is disconnected or floating, internal pull-up and VDD clamp (23.5 V) trigger safe auto-restart after 1 s, while COMP pin voltage (1–3 V range) directly governs burst mode entry (≤1.1 V) and peak current limiting (≤3 V).

Key Specifications

Pinout & Package

Available in DIP-7 and SSO10 packages; this variant uses DIP-7 with exposed drain pins (7 and 8) connected to metal frame for thermal dissipation. GND (pin 1), VDD (pin 2), LIM (pin 3), FB (pin 4), COMP (pin 5), and dual DRAIN (pins 7–8) form the functional interface. Pin 6 is NC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage offline PWM controller applications.

Compared with ICE2QS03G and LNK304P, VIPER06XN offers unique integration of 800 V ruggedness, self-biasing startup, and adjustable current limit - enabling simpler, lower-cost designs for sub-10 W applications where auxiliary winding elimination and thermal robustness are prioritized over integrated safety capacitors or higher-frequency operation.

Availability

VIPER06XN is available at Aetrix Electronics and suitable for smart home power supplies, LED lighting drivers, energy meter auxiliary supplies, and white goods control boards requiring stable component supply across industrial temperature ranges and long product lifecycles.

Supply support for VIPER06XN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for automotive, industrial, and consumer markets.

VIPER06XN belongs to ST's VIPerPlus family of high-voltage offline controllers, engineered specifically for cost-sensitive, space-constrained AC/DC converters demanding high reliability, low standby power, and simplified bill-of-materials in home appliance and IoT power applications.

FAQ

What is the minimum input voltage required to start up VIPER06XN?

VIPER06XN initiates startup when drain voltage reaches VDRAIN_START = 25–45 V (typ. 35 V), enabling reliable turn-on even with low-input AC conditions such as brownouts or partial rectification. The internal HV current generator begins charging VDD once this threshold is crossed, and switching commences when VDD rises above VDDon (12–14 V). No external bias source is needed.

Can VIPER06XN operate without an optocoupler in isolated flyback designs?

Yes - VIPER06XN supports primary-side sensing in isolated flyback configurations using a Zener-clamped auxiliary winding, eliminating the optocoupler and TL431. The FB pin is shorted to GND, and regulation is achieved by adjusting the auxiliary-to-secondary turns ratio so that VAUX reaches the internal VDD clamp (23.5 V) precisely at target VOUT, leveraging the device's open-loop failure protection.

How does the LIM pin adjust current limit, and what resistor value yields 0.2 A?

The LIM pin sinks current proportional to RLIM; Figure 14 in the datasheet shows IDlim ≈ 0.35 A × (1 − RLIM / 80 kΩ) for RLIM ≤ 80 kΩ. To achieve 0.2 A, RLIM ≈ 34 kΩ (calculated from linear interpolation of published curve). A standard 33 kΩ ±1% resistor yields ~0.205 A, verified under TJ = 25 °C with VCOMP = 3.3 V.

What thermal derating applies when using VIPER06XN in DIP-7 package on FR4?

In DIP-7 package on standard single-sided FR4 with 100 mm² copper (35 µm), RthJA = 90 °C/W. At TA = 50 °C, maximum allowable power dissipation is (150 °C − 50 °C) / 90 °C/W = 1.11 W. Since max rated PTOT is 1 W, full-rated operation is permitted up to 50 °C ambient; above that, linear derating applies at 11.1 mW/°C until TJ = 150 °C.