STMicroelectronics VIPER50ASPTR-E

Overview

VIPER50ASPTR-E from STMicroelectronics is a high-voltage, current-mode PWM controller with integrated 700 V vertical power MOSFET (R_DS(on) = 5.7 Ω, I_D = 1.5 A), designed for primary-side regulation in offline SMPS up to 50 W. It features adjustable switching frequency up to 100 kHz (typ.), burst-mode standby operation (<1 W total system consumption per Blue Angel norm), and built-in UVLO with 3 V hysteresis.

For engineers reviewing the VIPER50ASPTR-E datasheet, VIPER50ASPTR-E pinout, VIPER50ASPTR-E application, or VIPER50ASPTR-E equivalent, key selection considerations include its integrated start-up current source, transconductance error amplifier (G_m = 1.5 mA/V), thermal shutdown at 140–170 °C, and PENTAWATT HV package compatibility with snubberless flyback designs.

Technical Context

The VIPER50ASPTR-E implements a current-mode control topology using internal sense-FET current sensing and a transconductance error amplifier referenced to VDD. Peak current limiting is set by COMP pin voltage (1.4–2.6 V/A gain) with 250 ns blanking and 350 ns minimum on-time, enabling stable operation under line/load transients and short-circuit conditions.

Burst-mode stand-by is triggered when V_COMP falls below 0.5 V, forcing zero-duty-cycle shutdown until VDD recovers to 11 V (UVLO reset). The integrated 700 V MOSFET eliminates external HV start-up components, while oscillator synchronization via OSC pin supports multi-converter phase alignment without external timing ICs.

Key Specifications

Pinout & Package

PENTAWATT HV (022Y) package: 5-pin, high-voltage insulated thermally enhanced SIP, optimized for creepage/clearance in AC-DC converters.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICE2QS03G and LNK306P, VIPER50ASPTR-E uniquely combines integrated HV start-up, burst-mode standby, and OSC synchronization-enabling compact, eco-compliant, and system-coordinated power designs without external timing or protection ICs.

Availability

VIPER50ASPTR-E is available at Aetrix Electronics and suitable for USB wall adapters, smart home sensor power supplies, industrial PLC I/O modules, and white goods appliance control boards requiring stable component supply and long-term lifecycle support.

Supply support for VIPER50ASPTR-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, delivering intelligent power, analog, MEMS, and microcontroller solutions for industrial, automotive, and consumer markets.

VIPER™ is ST's dedicated high-voltage AC-DC converter product line, engineered for cost-effective, compact, and energy-efficient offline power supplies in sub-75 W applications.

FAQ

What is the maximum continuous output power achievable with VIPER50ASPTR-E in a flyback configuration?

The VIPER50ASPTR-E supports up to 50 W in single-range AC input (230 V_AC) or doubler configurations, and 25 W under universal input (85–265 V_AC). This is determined by its 700 V/1.5 A MOSFET, 5.7 Ω R_DS(on), and thermal limits (R_thJC = 1.9 °C/W). Derating is required above 70 °C ambient or with poor PCB copper area.

Can VIPER50ASPTR-E operate without an optocoupler in primary-side regulation?

Yes. VIPER50ASPTR-E supports primary-side regulation using VDD as feedback node-its internal 13 V reference regulates auxiliary winding voltage directly. No optocoupler or secondary-side TL431 is needed, reducing cost and improving reliability in low-to-mid power adapters and industrial supplies.

How does the burst-mode standby function reduce system power consumption?

Burst mode activates automatically when load power drops below ~0.5 W, causing V_COMP to fall below 0.5 V. This forces zero-duty-cycle shutdown until VDD recovers to 11 V, resulting in intermittent switching cycles. Combined with <2 mA quiescent current, this achieves <1 W total system standby power-compliant with Blue Angel and EU ERP Tier 2 standards.

Is external synchronization mandatory when using multiple VIPER50ASPTR-E devices on one board?

No, external synchronization is optional. The OSC pin supports synchronization only when required-for example, to avoid beat frequencies in multi-output supplies or meet strict EMI limits. In standalone operation, the internal oscillator (RT/CT configured) provides stable, jitter-free switching without external signals.