STMicroelectronics VIPER20A-22-E

Overview

VIPER20A-22-E from STMicroelectronics is a 700 V, 0.5 A integrated primary-side SMPS controller combining a current-mode PWM controller and a vertical high-voltage power MOSFET in a single PENTAWATT HV package. It delivers up to 10 W in universal-input offline power supplies, features adjustable 90–110 kHz switching frequency, internal 13 V VDD regulation, and burst-mode operation for <1 W standby consumption compliant with the German Blue Angel standard.

For engineers reviewing the VIPER20A-22-E datasheet, VIPER20A-22-E pinout, VIPER20A-22-E application, or VIPER20A-22-E equivalent, key selection considerations include its integrated 700 V MOSFET, programmable peak current limit (0.5–0.9 A), undervoltage lockout with 3 V hysteresis, thermal shutdown at 140–190 °C, and compatibility with both primary- and secondary-side regulation topologies.

Technical Context

This IC implements current-mode control using an internal transconductance error amplifier (Gm = 1.5 mA/V) and a dedicated current-sense comparator with 250 ns blanking time and 350 ns minimum on-time. The oscillator supports external RT/CT programming and synchronization via the OSC pin, maintaining stable frequency across 9–15 V VDD variations.

Startup is enabled by an integrated high-voltage current source connected to the DRAIN pin, delivering ~2 mA to charge the VDD capacitor until UVLO reset at 12 V; shutdown occurs at 8 V with 3 V hysteresis. Over-temperature protection latches off the MOSFET when junction temperature exceeds 170 °C typical, with 40 °C hysteresis for safe recovery.

Key Specifications

Pinout & Package

Package: PENTAWATT HV (022Y), 13-pin thermally enhanced SIP, optimized for high-voltage isolation and PCB heat dissipation in offline SMPS layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICE2QS03G and LNK304P, VIPER20A-22-E offers wider input voltage support, precise current limiting via COMP, and guaranteed <1 W standby without external components-making it optimal for universal-input, regulatory-compliant, mid-power designs.

Availability

VIPER20A-22-E is available at Aetrix Electronics and suitable for AC-DC wall adapters, smart home power supplies, industrial control modules, and white goods auxiliary supplies requiring stable component supply, long-term lifecycle support, and Blue Angel compliance.

Supply support for VIPER20A-22-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, designing and manufacturing microcontrollers, power ICs, sensors, and analog products for industrial, automotive, and consumer markets.

VIPER20A-22-E belongs to ST's VIPer™ family of integrated HV converters, engineered specifically for compact, low-component-count offline SMPS designs targeting energy-efficient standby performance and robust primary-side regulation.

FAQ

What is the purpose of the COMP pin in VIPER20A-22-E?

The COMP pin serves as the output of the transconductance error amplifier (1.5 mA/V typical) and functions as both the regulation interface and shutdown control. When connected to an RC network, it sets loop compensation; when pulled below 0.5 V, it forces zero-duty-cycle burst mode-enabling automatic low-power operation without external logic.

Can VIPER20A-22-E operate with primary-side regulation only?

Yes. VIPER20A-22-E supports primary-side regulation using its internal 13 V VDD reference and the COMP pin as a current source. This eliminates the need for an optocoupler and TL431, reducing cost and component count while maintaining ±5% output regulation across line and load in well-designed flyback transformers.

How does the integrated start-up current source work?

An internal high-voltage current source draws bias current directly from the DRAIN pin during startup, charging the external VDD capacitor until UVLO resets at 12 V. Once active, the source disables and the auxiliary winding sustains VDD. If auxiliary power fails, the device cycles between 8 V (shutdown) and 12 V (restart) with a 12% duty cycle, limiting stress during output shorts.

What thermal derating applies above 25°C case temperature?

With R_thJC = 2.0 °C/W and maximum T_J = 150 °C, the device delivers full 57 W power only at T_C = 25 °C. At T_C = 70 °C, usable power drops to ~32 W; at T_C = 100 °C, it falls to ~17 W. Layout must ensure adequate copper area per PENTAWATT HV thermal pad guidelines to maintain safe junction temperatures.