STMicroelectronics VIPER100A

Overview

VIPER100A from STMicroelectronics is a high-voltage, current-mode PWM controller with integrated 700 V vertical power MOSFET, designed for offline AC-DC primary-side SMPS. It delivers up to 100 W in single-range operation, features adjustable switching frequency up to 200 kHz, internal 13 V VDD regulation, and burst-mode standby operation compliant with Blue Angel (<1 W total consumption).

For engineers reviewing the VIPER100A datasheet, VIPER100A pinout, VIPER100A application, or VIPER100A equivalent, key selection considerations include its 700 V drain-source rating, 2.8 Ω R_DS(on) at 100 °C, integrated high-voltage startup current source, thermal shutdown at 140–170 °C, and COMP-pin–driven burst-mode control for ultra-low standby power.

Technical Context

The VIPER100A implements a fixed-frequency current-mode control architecture with an internal transconductance error amplifier (G_m = 1.5 mA/V), oscillator synchronized via external R_t/C_t, and PWM comparator with 250 ns blanking time and 1.7 µs disable setup delay. Its feedback path supports both primary and secondary regulation through the COMP pin.

Startup relies on an integrated high-voltage current source sourcing from the DRAIN pin, enabling snubberless operation. Undervoltage lockout (UVLO) operates with 8 V turn-off and 12 V reset thresholds and 3 V hysteresis, while overtemperature protection triggers at 140–170 °C with 40 °C hysteresis and forces latch-off.

Key Specifications

Pinout & Package

Package: PENTAWATT HV (022Y), 5-pin, high-voltage insulated plastic package with exposed metal tab for thermal dissipation (R_thj-case = 1.4 °C/W).

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 uniquely combines 700 V ruggedness, integrated HV startup, adjustable frequency, and certified <1 W standby-making it optimal for mid-power (30–100 W), regulatory-compliant, and snubberless flyback designs.

Availability

VIPER100A is available at Aetrix Electronics and suitable for smartphone charger adapters, LED driver power supplies, industrial sensor modules, and white goods auxiliary supplies requiring stable component supply and long-term design-in support.

Supply support for VIPER100A 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™ family is engineered for highly integrated, cost-optimized AC-DC conversion-targeting offline SMPS designs where integration, reliability, and regulatory compliance (e.g., Blue Angel, CoC) are critical.

FAQ

What is the maximum continuous output power achievable with VIPER100A in a flyback converter?

The VIPER100A supports up to 100 W in single-range (230 V_AC) or doubler configurations, and 50 W in universal-input (85–265 V_AC) wide-range operation. Actual output depends on transformer design, heatsinking, and ambient temperature-derating is required above 70 °C case temperature due to its 1.4 °C/W thermal resistance.

Can VIPER100A operate without an auxiliary winding on the transformer?

Yes-the integrated high-voltage startup current source draws bias from the DRAIN pin during initial power-up, eliminating the need for an auxiliary winding. Once running, the device can be self-sustained via V_DD regulation, though an auxiliary winding improves efficiency and stability under dynamic load conditions.

How does burst mode operation reduce standby power consumption?

Burst mode activates automatically when load demand drops below ~1 W: the COMP pin voltage falls below 0.5 V, forcing zero-duty-cycle shutdown. The device remains off until V_DD decays to the UVLO turn-on threshold (12 V), then delivers a short energy burst before re-entering shutdown-reducing average input power to <1 W while maintaining output regulation.

Is VIPER100A pin-compatible with VIPER100/SP?

No-while functionally similar, VIPER100A (700 V, 2.8 Ω) and VIPER100/SP (620 V, 2.5 Ω) share the same PENTAWATT HV package and pinout, but differ in absolute maximum ratings and electrical characteristics. Direct substitution requires validation of voltage stress margins, thermal performance, and current-limit settings in the target application.