STMicroelectronics STSR2PCD-TR

Overview

STSR2PCD-TR from STMicroelectronics is a smart synchronous rectifier driver IC designed for secondary-side gate control in medium-power forward converters. It delivers complementary high-current outputs (−2A source / 3.5A sink), operates from 4.5V–5.5V supply, supports 20–750kHz switching, and implements smart turn-off anticipation to prevent shoot-through in low-voltage, high-efficiency DC/DC systems.

For engineers reviewing the STSR2PCD-TR datasheet, STSR2PCD-TR pinout, STSR2PCD-TR application, or STSR2PCD-TR equivalent, key selection considerations include its dual-gate timing independence from magnetic reset technique, programmable OUTGATE2 turn-off anticipation via SETANT2, INHIBIT-enabled discontinuous conduction mode, and SO-8 package compatibility with high-density power layouts.

Technical Context

The STSR2PCD-TR integrates a 15MHz internal oscillator synchronized to an external clock (CK) to generate precisely timed, dead-time-controlled complementary gate drives for synchronous rectifier MOSFETs. Its cycle-by-cycle control logic ensures safe turn-off transitions independent of forward converter demagnetization method.

It features two distinct turn-off anticipation mechanisms: fixed 75ns anticipation on OUTGATE1 at CK falling edge, and externally adjustable tANT2 (75/150/225ns) on OUTGATE2 via voltage division on SETANT2. The INHIBIT function enables dynamic disable of OUTGATE2 to support DCM and prevent reverse current flow during light-load conditions.

Key Specifications

Pinout & Package

STSR2PCD-TR is housed in a standard SO-8 surface-mount package (5.0 × 4.0 mm, 1.27 mm pitch) with separate SGLGND (signal ground) and PWRGND (power ground) pins to isolate noise-sensitive control circuitry from high di/dt paths.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous rectifier driver applications.

Compared with MP6908GJ-Z and UCC24612-2QDRQ1, STSR2PCD-TR uniquely combines dual-output programmable anticipation, INHIBIT-based DCM, and reset-technique independence in a compact SO-8 package-making it optimal for high-efficiency, thermally constrained forward converters where timing precision and layout simplicity are critical.

Availability

STSR2PCD-TR is available at Aetrix Electronics and suitable for forward converter secondary-side gate driving, low-voltage high-current DC/DC modules, and high-efficiency industrial power supplies requiring stable component supply and long-term production continuity.

Supply support for STSR2PCD-TR 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, analog, microcontrollers, and automotive ICs with manufacturing and R&D across Europe, Asia, and the Americas.

The STSR2P series was developed specifically for high-efficiency isolated DC/DC conversion, targeting forward converter topologies where precise, independent control of synchronous rectifier timing improves efficiency, thermal performance, and system reliability.

FAQ

What is the purpose of the separate SGLGND and PWRGND pins?

SGLGND provides a clean reference for all internal comparators, oscillators, and logic circuits, while PWRGND carries high di/dt return currents from both gate drivers. This separation prevents switching noise from corrupting timing accuracy or causing false INHIBIT/CK detection-critical for stable operation in noisy power environments.

How does the INHIBIT function enable discontinuous conduction mode?

When the INHIBIT pin voltage rises above −25 mV (indicating impending reverse inductor current), the IC forces OUTGATE2 into a high-impedance state after a guaranteed minimum on-time (250 ns). This prevents the freewheeling MOSFET from conducting reverse current, allowing the inductor current to fall to zero and enabling true DCM operation.

Can STSR2PCD-TR operate with non-standard forward transformer reset techniques?

Yes. Its internal 15 MHz oscillator synchronizes to the CK input using a fixed positive threshold, making timing behavior independent of whether the forward converter uses RCD clamp, active clamp, or resonant reset. This eliminates timing jitter and false triggering common in self-driven synchronous rectifier solutions.

What is the significance of the 13% duty-cycle shutdown feature?

This feature disables both gate outputs when the measured duty cycle falls below 13%, reducing quiescent current consumption and preventing erratic gate behavior during very light loads or startup. It re-enables automatically once duty cycle exceeds 18%, ensuring seamless transition back to normal operation without external intervention.