STMicroelectronics VIPER17HDTR

Overview

VIPER17HDTR from STMicroelectronics is a high-voltage (800 V) integrated flyback switching regulator IC combining an avalanche-rugged N-channel power MOSFET, current-mode PWM controller, and multiple protection circuits in a single SO16 narrow package. It delivers up to 10 W in open-frame designs at 50 °C ambient, supports 115 kHz switching with ±8 kHz jittering for EMI reduction, achieves <30 mW standby power at 265 VAC, and features adjustable cycle-by-cycle current limit via the CONT pin - used in auxiliary power supplies for LCD TVs, LED drivers, and set-top boxes.

For engineers reviewing the VIPER17HDTR datasheet, VIPER17HDTR pinout, VIPER17HDTR application, or VIPER17HDTR equivalent, key selection criteria include its 800 V drain-source breakdown voltage, 115 kHz nominal operating frequency, burst-mode operation for ultra-low no-load consumption, brown-out protection with 0.45 V threshold, and integrated soft-start with 8.5 ms ramp time - all critical for energy-compliant offline SMPS design.

Technical Context

The VIPER17HDTR implements a fixed-frequency current-mode PWM control architecture with built-in high-voltage startup (80–100 V drain start threshold), digitally filtered overvoltage protection strobed every 2.2 µs, and dual-level overcurrent protection including hiccup-mode second-stage shutdown at 0.6 A. Its oscillator provides 115 kHz nominal frequency with 250 Hz spread-spectrum modulation depth of ±8 kHz to suppress EMI peaks.

Control logic integrates a 3.3 V feedback reference with burst-mode activation below 0.45 V on FB, linear regulation range up to 3.4 V, and overload shutdown at 4.8 V. The CONT pin enables either current-limit adjustment (via external resistor) or output voltage monitoring, while BR pin provides hysteresis-based brown-out detection with 50 mV hysteresis and 12 µA hysteresis current.

Key Specifications

Pinout & Package

VIPER17HDTR is housed in a SO16 narrow (SOIC-16) surface-mount package with exposed thermal pad connected to pins 7–16 (DRAIN). The package supports 1 W power dissipation at TA < 60 °C with 110 °C/W junction-to-ambient thermal resistance on standard FR4 board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage flyback controller applications.

Compared with ICE2QS03G and LNK306P, VIPER17HDTR uniquely combines 800 V ruggedness, 115 kHz jittered operation, adjustable current limit, and digital OVP in one SO16 package - making it optimal for compact, globally compliant, and thermally constrained offline SMPS where design flexibility and protection robustness are prioritized.

Availability

VIPER17HDTR is available at Aetrix Electronics and suitable for adapter power supplies, auxiliary power for LCD TVs, LED drivers, and SMPS for consumer electronics requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for VIPER17HDTR 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 devices for automotive, industrial, and consumer markets.

VIPER17 belongs to ST's VIPerPlus family of high-voltage off-line controllers engineered specifically for compact, energy-efficient flyback converters in sub-15 W applications - emphasizing integration, protection robustness, and regulatory compliance.

FAQ

What is the purpose of the CONT pin on VIPER17HDTR?

The CONT pin serves dual functions: it adjusts the cycle-by-cycle current limit threshold via an external resistor to match transformer design, or monitors the auxiliary winding voltage for digitally filtered overvoltage protection. When used for OVP, it samples during MOSFET off-time with 2.2 µs strobe delay to reject switching noise, triggering auto-restart after four consecutive violations of the 3.0 V threshold.

How does VIPER17HDTR achieve <30 mW standby power?

VIPER17HDTR achieves ultra-low standby power through burst-mode operation activated when FB voltage falls below 0.45 V, reducing average switching frequency; combined with <270 µA quiescent current in UVLO state, integrated HV startup eliminating auxiliary winding losses, and efficient 800 V power MOSFET with 24 Ω RDS(on) at 25 °C - all enabling compliance with stringent global energy regulations.

Can VIPER17HDTR replace VIPER17HN in a DIP-7 design?

No - VIPER17HDTR uses SO16 narrow package with different pinout, thermal pad layout, and solder-reflow requirements versus the through-hole DIP-7 VIPER17HN. While electrical functionality is identical, mechanical compatibility is not assured; redesign of PCB footprint, thermal relief, and assembly process is required for substitution.

What is the role of the BR pin and how should it be configured?

The BR pin implements brown-out protection by monitoring bulk DC voltage via a resistive divider; it shuts down switching when voltage falls below 0.45 V (with 50 mV hysteresis) and resumes operation once voltage rises above 0.50 V. If brown-out protection is not needed, BR must be connected directly to GND - leaving it floating may cause erratic behavior due to noise susceptibility.