STMicroelectronics VIPER100A-E

Overview

VIPER100A-E from STMicroelectronics is a high-voltage, current-mode PWM controller with integrated 700 V/3 A vertical power MOSFET, designed for primary-side offline SMPS in wide-range (85–265 VAC) and single-range (230 VAC) applications. It delivers up to 50 W in universal input and 100 W in single-input or voltage-doubler configurations, features adjustable 90–110 kHz switching frequency, internal 13 V VDD regulation, and burst-mode operation enabling <1 W standby power per Blue Angel requirements.

For engineers reviewing the VIPER100A-E datasheet, VIPER100A-E pinout, VIPER100A-E application, or VIPER100A-E equivalent, key selection criteria include its integrated HV start-up current source, 2.8 Ω R_DS(on) at 100 °C, 1.7 µs disable setup time, 250 ns current-sense blanking, and thermal shutdown at 140–170 °C - all critical for robust, low-component-count AC-DC converter design.

Technical Context

The VIPER100A-E implements a current-mode control topology using a transconductance error amplifier (G_m = 1.5 mA/V typ.) and a PWM comparator with 0.5 V offset and 1 V/A gain. Its oscillator supports external RT/CT programming and synchronization via the OSC pin, with frequency stability over VDD = 9–15 V and ±1% resistor / ±5% capacitor tolerance.

It integrates an undervoltage lockout (UVLO) with 8 V turn-off and 12 V reset (3 V hysteresis), overtemperature protection (140–170 °C trip, 40 °C hysteresis), and a high-voltage start-up current source sourced from the DRAIN pin - eliminating external bias windings in many designs.

Key Specifications

Pinout & Package

Package: PENTAWATT HV (PowerSO-10™, 022Y footprint), thermally enhanced 10-pin surface-mount package with exposed drain pad for direct PCB heat sinking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICE2QS03G and LNK306P, the VIPER100A-E uniquely combines 700 V/3 A integration, adjustable frequency, internal HV start-up, and certified <1 W standby - making it optimal for mid-power (30–100 W), regulatory-compliant offline converters where component count and thermal performance are critical.

Availability

VIPER100A-E is available at Aetrix Electronics and suitable for USB wall adapters, smart home power supplies, industrial sensor transmitters, and LED driver auxiliary supplies requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for VIPER100A-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/mixed-signal ICs for industrial, automotive, and consumer markets.

The VIPer™ product line delivers highly integrated, high-voltage AC-DC controllers targeting cost-sensitive, space-constrained offline power supplies - emphasizing reduced external component count, robust protection features, and regulatory compliance out-of-the-box.

FAQ

What is the maximum continuous output power achievable with VIPER100A-E in universal input (85–265 VAC) conditions?

The VIPER100A-E supports up to 50 W of continuous output power in wide-range AC input applications when implemented with appropriate transformer design, heatsinking, and layout. This rating assumes operation at full load with junction temperature maintained below 125 °C, using the 2.8 Ω R_DS(on) and 82 W P_tot thermal limit. Derating is required above 70 °C ambient or with poor PCB copper area.

How does the burst mode operation reduce standby power consumption?

Burst mode activates automatically when output load drops below ~0.5 W, causing the COMP pin voltage to fall below 0.5 V. This forces zero-duty-cycle shutdown until VDD recovers to 12 V, resulting in intermittent switching cycles. The effective duty cycle drops to ~12%, reducing average input current and enabling total system standby power below 1 W - compliant with Blue Angel and Energy Star Level VI requirements.

Can VIPER100A-E be used with secondary-side regulation via optocoupler feedback?

Yes - the VDD pin serves dual roles: as the internal 13 V regulator reference and as the error amplifier input node. When configured for secondary regulation, the optocoupler output connects to the COMP pin, while VDD is supplied externally (8.5–12.5 V) from the auxiliary winding. The transconductance amplifier then operates in constant-current mode, enabling precise cross-regulation without additional components.

What is the purpose of the 250 ns blanking time, and how is it implemented?

The 250 ns blanking time disables the current-sense comparator immediately after the MOSFET turns on, preventing false overcurrent trips caused by parasitic ringing from transformer leakage inductance or secondary rectifier reverse recovery. It is hardwired into the silicon and cannot be adjusted; this fixed delay ensures reliable operation across all loads and input voltages without external timing components.