STMicroelectronics VIPER16LN

Overview

VIPER16LN from STMicroelectronics is an 800 V avalanche-rugged off-line PWM controller IC with integrated high-voltage power MOSFET, fixed 60 kHz switching frequency, adjustable overcurrent limit via LIM pin, and self-biasing capability eliminating auxiliary winding requirements. It delivers up to 9 W in non-ventilated adapters and supports flyback, buck, and buck-boost topologies for low-power AC/DC conversion.

For engineers reviewing the VIPER16LN datasheet, VIPER16LN pinout, VIPER16LN application, or VIPER16LN equivalent, this device is selected for energy-efficient auxiliary supplies in smart meters, LED drivers, and white goods where <30 mW standby power, thermal robustness, and EMI reduction via frequency jittering are critical design requirements.

Technical Context

The VIPER16LN integrates a SenseFET-based current-sensing architecture and hysteretic thermal shutdown (TSD = 150–160 °C) with 30 °C hysteresis, enabling safe auto-restart after fault conditions without external circuitry. Its internal high-voltage start-up generator draws current directly from the DRAIN pin at VDRAIN_START (40–60 V), enabling direct mains connection.

It implements burst-mode operation triggered when COMP pin voltage falls below VCOMPL (1.1 V typ.), reducing average switching frequency to hundreds of Hz and limiting peak drain current to 85 mA during light load - directly supporting compliance with EU ErP Lot 6 and ENERGY STAR standby power regulations.

Key Specifications

Pinout & Package

Package: DIP-7 (dual-in-line plastic, 7-pin), with pins 7 and 8 internally connected to the metal frame for enhanced thermal dissipation. Copper pour under DRAIN pins is mandatory per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar off-line PWM controller applications.

Compared with ICE2QS03G and VIPER06XS, VIPER16LN offers the lowest system-level BOM count and best-in-class standby power for sub-10 W applications, trading off some thermal margin and peak efficiency for simplicity and regulatory compliance out-of-the-box.

Availability

VIPER16LN is available at Aetrix Electronics and suitable for smart energy metering, LED lighting drivers, home appliance control boards, and industrial sensor power supplies requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for VIPER16LN 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 silicon solutions for automotive, industrial, and power management applications.

VIPER16LN belongs to the VIPer™ plus family of high-voltage off-line controllers, engineered specifically for cost-sensitive, low-to-mid power AC/DC conversion where integration, reliability, and energy efficiency are prioritized over programmability or digital control.

FAQ

What is the maximum continuous output power achievable with VIPER16LN in an open-frame design?

VIPER16LN delivers up to 6 W continuously in an open-frame configuration at 50 °C ambient with adequate heat sinking, as confirmed in Table 2 of the official datasheet (DocID15232 Rev 7). This assumes proper PCB copper area under DRAIN pins and adherence to thermal resistance guidelines (RthJA = 90 °C/W on FR4 with 100 mm² Cu).

Can VIPER16LN operate without an optocoupler in isolated flyback designs?

No - in isolated flyback configurations, the internal error amplifier must be disabled (FB pin shorted to GND), and regulation relies on an external optocoupler feeding current into the COMP pin. The datasheet explicitly states that isolated operation requires closing the feedback loop via the opto-transistor in parallel with the compensation network.

How does the LIM pin adjust the current limit, and what resistor value yields 0.25 A IDlim?

The LIM pin sinks current proportional to external RLIM; Figure 13 shows IDlim ≈ 0.4 A × (1 − RLIM / 80 kΩ) for RLIM ≤ 80 kΩ. To achieve 0.25 A, RLIM ≈ 30 kΩ is required (0.25 = 0.4 × (1 − RLIM/80)). Values above 80 kΩ revert to default 0.4 A, and capacitors ≤470 nF may be added for noise immunity.

Is VIPER16LN RoHS-compliant and halogen-free?

Yes - VIPER16LN is manufactured in STMicroelectronics' RoHS-compliant and halogen-free processes, as documented in the "Package mechanical data" section (page 25) and "Revision history" (page 29) of DocID15232 Rev 7, with full compliance to EU Directive 2011/65/EU and JEDEC JS709B.