STMicroelectronics VIPER100-E

Overview

VIPER100-E from STMicroelectronics is a high-voltage, current-mode PWM controller with integrated 620 V/3 A vertical power MOSFET, designed for primary-side switching in offline AC-DC flyback converters. It delivers up to 100 W in single-range operation, features adjustable 90–110 kHz switching frequency, internal 13 V VDD regulation, and burst-mode standby operation compliant with Germany's "Blue Angel" <1 W requirement.

For engineers reviewing the VIPER100-E datasheet, VIPER100-E pinout, VIPER100-E application, or VIPER100-E equivalent, key selection considerations include its integrated HV start-up current source, programmable peak current limit (3–5.3 A), thermal shutdown at 140–170 °C, and PENTAWATT HV (022Y) package compatibility with high-voltage primary-side PCB layouts.

Technical Context

The VIPER100-E implements a current-mode control topology with dual-loop regulation: an inner loop monitors primary peak current via sense-FET technique and compares it to the COMP pin voltage, while the outer loop uses transconductance error amplification (G_m = 1.1–1.9 mA/V) to adjust duty cycle. Its oscillator supports external synchronization via the OSC pin and maintains stable frequency (±1% RT, ±5% CT tolerance) across 9–15 V VDD range.

Standby operation is enabled by automatic burst mode triggered when V_COMP falls below 0.5 V, forcing zero-duty-cycle shutdown until VDD recovers to ≥11 V. Overtemperature protection activates at 140–170 °C with 40 °C hysteresis, and undervoltage lockout includes 2.4–3 V hysteresis between 7.5–9 V shutdown and 11–12 V reset thresholds.

Key Specifications

Pinout & Package

The VIPER100-E is housed in a PENTAWATT HV (022Y) package - a 5-pin, high-voltage-optimized surface-mount package with extended creepage/clearance and isolated drain tab for direct heatsinking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar primary-side PWM controller applications.

Compared with ICE2QS03G and LNK306P, the VIPER100-E uniquely balances medium-power capability (50–100 W), integrated HV start-up, and programmable burst mode-making it optimal for universal-input 24–48 V industrial and appliance auxiliary supplies where reliability and regulatory compliance are critical.

Availability

VIPER100-E is available at Aetrix Electronics and suitable for AC-DC adapters, smart home power supplies, industrial control PSUs, and white goods auxiliary supplies requiring stable component supply and long-term lifecycle support.

Supply support for VIPER100-E 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, specializing in power management, microcontrollers, and analog ICs for industrial, automotive, and consumer markets.

The VIPer™ product line delivers highly integrated, high-voltage AC-DC converter ICs targeting cost-effective, compact, and safety-compliant offline power supplies for universal-input applications.

FAQ

What is the maximum continuous output power achievable with VIPER100-E in a flyback design?

The VIPER100-E supports up to 50 W in universal-input (85–265 VAC) wide-range configurations and up to 100 W in single-range (230 VAC) or doubler configurations. Achievable power depends on transformer design, heatsinking, and ambient temperature-derating is required above 70 °C case temperature due to its 1.4 °C/W junction-to-case thermal resistance.

Can VIPER100-E operate with primary-side regulation only, without an optocoupler?

Yes. The VIPER100-E supports primary-side regulation using its internal 13 V VDD reference and feedback derived from auxiliary winding voltage. This eliminates the optocoupler and TL431, reducing cost and improving reliability-though accuracy is typically ±5%, versus ±1% with secondary-side regulation.

How does the internal blanking time prevent false current-limit triggering?

The VIPER100-E applies a fixed 250–360 ns blanking window after each MOSFET turn-on to ignore initial current spikes caused by transformer leakage inductance and secondary rectifier reverse recovery. This ensures the PWM comparator only responds to true primary current ramp, preventing premature switch-off and instability in DCM operation.

Is external synchronization of the oscillator supported, and what are the drive requirements?

Yes-the OSC pin accepts external clock signals for synchronization. A clean TTL/CMOS pulse with ≤500 ns width, 3–5 V amplitude, and ≤20 mA sink capability (e.g., via fast optocoupler) is required. The external signal overrides the internal oscillator, enabling multi-channel interleaving or EMI spreading without modifying RT/CT components.