STMicroelectronics VIPER53SP

Overview

VIPER53SP from STMicroelectronics is an integrated offline primary switch combining a current-mode PWM controller and a 620 V high-voltage MDMesh™ Power MOSFET in PowerSO-10™ package. It delivers up to 40 W output power under single European input (195–265 Vac), features adjustable current limitation, automatic burst-mode standby (<0.5 W input), and built-in overtemperature/overvoltage/short-circuit protection. It targets compact AC/DC adapters and auxiliary power supplies for industrial controls and consumer electronics.

For engineers reviewing the VIPER53SP datasheet, VIPER53SP pinout, VIPER53SP application, or VIPER53SP equivalent, key selection considerations include its 620 V drain-source rating, 1.7–2.3 A peak current limit, 100 kHz typical switching frequency, thermal shutdown at 140–160 °C, and PowerSO-10™ thermal resistance of 2 °C/W (junction-to-case).

Technical Context

The VIPER53SP implements a current-mode control architecture with cycle-by-cycle peak current sensing via internal SenseFET and COMP pin voltage feedback. Its PWM latch, blanking timer (100–500 ns), and adjustable minimum on-time (250–750 ns) enable stable operation across wide load and line variations.

It integrates a high-voltage startup current source (−12 mA at VDD = 0–5 V), undervoltage lockout with 3.1 V hysteresis (11.5 V turn-on / 8.4 V turn-off), and a transconductance error amplifier (1.4 mS typical, 700 kHz GBW) supporting both primary-regulated and optocoupler-based secondary regulation topologies.

Key Specifications

Pinout & Package

Package: PowerSO-10™ - Exposed tab thermally connected to DRAIN, enabling low R_thj-case = 2 °C/W when soldered to ≥50 mm² copper pour.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar offline primary switch applications.

Compared with VIPER53SP, STVIPER06 offers lower conduction loss but sacrifices programmable protection and burst-mode accuracy, while ICE3B0565J improves standby efficiency via QR topology but adds layout complexity and loses the integrated HV startup source.

Availability

VIPER53SP is available at Aetrix Electronics and suitable for industrial control panels, smart meter auxiliary supplies, white goods mainboard PSUs, and LED driver bias circuits requiring stable component supply and long-term lifecycle support.

Supply support for VIPER53SP 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/mixed-signal ICs for industrial, automotive, and consumer markets.

The VIPer™ family was designed specifically for highly integrated, low-component-count offline SMPS solutions-targeting cost, size, and reliability constraints in AC/DC adapter and auxiliary supply applications.

FAQ

What is the maximum continuous output power achievable with VIPER53SP in a European-input (230 Vac) flyback design?

The VIPER53SP supports up to 40 W output power under 195–265 Vac input when mounted on a standard FR4 PCB with ≥50 mm² copper connected to the exposed DRAIN tab (R_thj-case = 2 °C/W). This assumes proper transformer design, adequate heatsinking, and operation within the 100 kHz switching frequency range. Derating is required above 85 °C ambient or with reduced copper area.

How does the TOVL pin function, and what capacitor value is recommended for standard overload protection?

The TOVL pin accepts an external capacitor that sets the delay time before overload shutdown is triggered when COMP exceeds 4.35 V. With a 100 nF capacitor, the delay is 8 ms (per Figure 4). A 1 kΩ series resistor is recommended to improve ruggedness against drain overvoltage transients. The capacitor value scales linearly with delay time-e.g., 47 nF yields ~3.8 ms delay.

Can VIPER53SP operate without an optocoupler, and how is output voltage regulated in that configuration?

Yes. In primary-regulated mode, the auxiliary winding feeds VDD, and the internal error amplifier regulates it precisely to 15 V. Output voltage is set by the turns ratio between the auxiliary and secondary windings. Load regulation depends only on transformer coupling and rectifier impedance-not optocoupler gain-making this configuration simpler and more reliable for non-critical outputs.

What is the purpose of the blanking time function, and how does it vary with COMP voltage?

The blanking time (100–500 ns) disables the PWM comparator immediately after switch turn-on to ignore current spikes from transformer leakage inductance or diode reverse recovery. It changes based on COMP voltage: below 1 V (V_COMPbl), blanking is 400 ns (yielding 600 ns min on-time); above 1 V, it drops to 150 ns (350 ns min on-time), creating hysteresis that stabilizes burst-mode transitions.