STMicroelectronics VIPER319HDTR

Overview

VIPER319HDTR from STMicroelectronics is an integrated 800 V avalanche-rugged high-voltage PWM controller with embedded power MOSFET, designed for offline flyback, buck, and buck-boost SMPS. It delivers up to 31 W in open-frame designs at 50°C ambient, features 990 mA drain current limit (typ.), 132 kHz ±7% jittered switching frequency, and <20 mW no-load input power at 230 VAC - enabling compliance with stringent energy-saving standards in compact low-power adapters.

For engineers reviewing the VIPER319HDTR datasheet, VIPER319HDTR pinout, VIPER319HDTR application, or VIPER319HDTR equivalent, key selection considerations include its 800 V MOSFET breakdown rating, integrated HV startup current source (8.8 mA typ.), 1.2 V internal error amplifier reference, thermal shutdown at 150°C, and OVP/UVP threshold programmability via external resistive dividers.

Technical Context

The VIPER319HDTR implements a current-mode PWM control architecture with built-in soft-start (8 ms typ.), pulse-frequency modulation (PFM) at light load, and jittered oscillator (±7% spread spectrum at 200 Hz) to reduce EMI filter cost. Its embedded sense-FET enables lossless primary-side current sensing without external shunt.

Protection logic includes auto-restart OLP (50 ms overload delay), thermal shutdown (150°C threshold), and overvoltage protection (4 V OVP threshold, 500 ms restart delay), plus non-auto-restart features like pulse-skip to prevent flux runaway and UVLO disable (0.4 V UVP threshold, 30 ms debounce).

Key Specifications

Pinout & Package

Package: SO-16N (16-pin small outline, exposed drain pad for thermal dissipation). Thermal resistance: 5 °C/W junction-to-case (with 100 mm² copper area), enabling high-power density in space-constrained adapters.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICE3B0565J and LNK3206P, VIPER319HDTR offers superior input voltage margin (800 V), lowest no-load consumption, and highest integration (HV startup, E/A, jitter), making it optimal for next-gen energy-compliant adapters and space-constrained industrial PSUs.

Availability

VIPER319HDTR is available at Aetrix Electronics and suitable for low-power SMPS in home appliances, industrial sensor nodes, and lighting drivers requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for VIPER319HDTR 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, delivering innovative analog, MCU, power, and sensor solutions for automotive, industrial, and consumer markets.

VIPER31 is part of ST's high-voltage offline AC-DC converter product line, engineered specifically for compact, energy-efficient, and cost-optimized power supplies in sub-30 W applications - emphasizing integration, reliability, and regulatory compliance.

FAQ

What is the maximum continuous output power achievable with VIPER319HDTR?

VIPER319HDTR delivers up to 31 W in open-frame configurations at 50°C ambient temperature with adequate heatsinking, and 27 W in non-ventilated enclosed adapters. This is validated per ST's DS13285 Rev 6 test conditions using 85–265 VAC input, flyback topology, and SO-16N package mounted on 100 mm² copper area.

How does the jittered oscillator reduce EMI in practical PCB layouts?

The ±7% frequency modulation at 200 Hz spreads spectral energy across adjacent bands, lowering peak conducted emissions by 5–10 dB compared to fixed-frequency operation. This allows reduction of common-mode choke size and Y-capacitor values - verified in ST application note AN4170 using CISPR-22 average detection.

Can VIPER319HDTR operate without an auxiliary winding for VCC supply?

Yes - its integrated 800 V HV startup current source charges the VCC capacitor directly from the DRAIN pin, eliminating the need for an auxiliary winding in most designs. An auxiliary winding is only required for sustained high-load operation or when VCC dropout risk exists during deep line sags.

What is the role of the four DRAIN pins (13–16) in thermal management?

Pins 13–16 are electrically and thermally paralleled to the internal MOSFET drain and connected to the exposed metal pad. Routing wide copper pours beneath these pins reduces junction-to-ambient thermal resistance from 120 °C/W to 85 °C/W (per DS13285), enabling higher power density without external heatsinks.