STMicroelectronics VIPER53SPTR-E

Overview

VIPER53SPTR-E from STMicroelectronics is an integrated offline primary switch combining a current-mode PWM controller and a 620 V MDMesh™ Power MOSFET in a single DIP-8 package. It delivers up to 30 W at universal input (85–265 VAC), features adjustable peak current limiting (2.0 A typ.), 100 kHz oscillator frequency (±5%), and built-in thermal shutdown (160 °C). It is designed for compact, low-cost AC/DC flyback converters in consumer adapters and auxiliary power supplies.

For engineers reviewing the VIPER53SPTR-E datasheet, VIPER53SPTR-E pinout, VIPER53SPTR-E application, or VIPER53SPTR-E equivalent, key selection considerations include its integrated high-voltage startup current source (−12 mA), primary-side regulation capability via VDD error amplifier (15 V regulated), automatic burst-mode standby (<0.5 W), and overload protection with 8 ms delay via TOVL capacitor timing.

Technical Context

The VIPER53SPTR-E implements a current-mode control topology with cycle-by-cycle peak drain current sensing referenced to the COMP pin voltage (0.5–4.5 V range) and a fixed blanking time (300–500 ns) to suppress transformer leakage spikes. Its transconductance error amplifier (1.4 mS typ.) regulates VDD at 15 V in primary-feedback mode, enabling stable output without optocoupler dependency.

Standby operation uses a dedicated comparator monitoring COMP voltage <0.5 V to disable switching and enter burst mode-reducing no-load consumption while maintaining output regulation. Overtemperature protection triggers at 160 °C with 40 °C hysteresis, and undervoltage lockout operates between 8.4 V (shutdown) and 11.5 V (startup), ensuring robust start-up under brownout conditions.

Key Specifications

Pinout & Package

Package: DIP-8 (dual in-line plastic, 7.62 mm pitch), through-hole mount, with internal MOSFET drain connected to pin 5 (DRAIN) and source tied to pins 1 & 4 (SOURCE).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICE3B0565J and LNK306P, the VIPER53SPTR-E uniquely integrates primary-side regulation, programmable blanking, and Blue Angel-compliant burst mode-enabling simpler, more efficient, and standards-ready 30 W flyback designs without secondary feedback components.

Availability

VIPER53SPTR-E is available at Aetrix Electronics and suitable for USB wall adapters, smart home sensor power supplies, white goods control board aux PS, and industrial PLC I/O module power requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for VIPER53SPTR-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, specializing in power management, microcontrollers, and analog ICs for industrial, automotive, and consumer markets.

The VIPer™ product line delivers highly integrated AC/DC primary controllers targeting cost-sensitive, space-constrained offline power supplies-emphasizing integration, safety compliance, and ease of certification.

FAQ

What is the minimum external capacitor required on the COMP pin?

A minimum 8 nF ceramic capacitor must be placed between COMP (pin 6) and SOURCE (pins 1/4) to ensure stability of the transconductance error amplifier. The typical value used is 10 nF. Omitting this capacitor causes oscillation and loss of regulation, as confirmed in Figure 14 and Section 11 of the official datasheet.

Can VIPER53SPTR-E operate without an optocoupler?

Yes-it supports primary-side regulation by using the internal error amplifier to regulate the auxiliary winding's VDD voltage to 15 V. Output voltage is set by the transformer turns ratio between auxiliary and secondary windings, eliminating optocoupler dependency for basic regulation accuracy (±5%).

How does the TOVL pin implement overload protection?

The TOVL pin connects an external capacitor (e.g., 100 nF) that sets an 8 ms delay before shutdown when COMP exceeds 4.35 V. This prevents nuisance tripping during transient overloads while ensuring reliable protection during sustained faults, as detailed in Figure 4 and Table 8 of the datasheet.

What is the purpose of the dual blanking time (tb1/tb2)?

The blanking time changes based on COMP voltage: 300–500 ns when COMP < 1 V (tb1) and 100–200 ns when COMP > 1 V (tb2). This adaptive blanking suppresses turn-on spikes during light loads (high tb1) while minimizing dead-time penalty at heavy loads (low tb2), improving efficiency across operating range.