STMicroelectronics STSR2PMCD

Overview

STSR2PMCD from STMicroelectronics is a dual-channel synchronous rectifier smart driver IC designed for secondary-side gate control in medium-power forward converters. It delivers complementary high-current outputs (source −2 A, sink 3.5 A), operates from 4.5–5.5 V supply, supports 20–750 kHz switching, and features programmable turn-off anticipation timing to prevent shoot-through in low-voltage, high-efficiency DC-DC systems.

For engineers reviewing the STSR2PMCD datasheet, STSR2PMCD pinout, STSR2PMCD application, or STSR2PMCD equivalent, this device is selected for precise timing-critical synchronous rectification where duty-cycle resilience, independent magnetic reset operation, and discontinuous conduction mode (DCM) support are required.

Technical Context

The STSR2PMCD implements cycle-by-cycle dead-time control using a synchronized 15 MHz internal oscillator and smart clock revelation logic, enabling robust operation across varying demagnetization techniques. Its dual-output architecture provides independent turn-off anticipation: fixed 75 ns for OUTGATE1 and externally adjustable (75/150/225 ns) for OUTGATE2 via SETANT2 voltage partitioning.

An integrated inhibit function allows dynamic shutdown of OUTGATE2 during reverse freewheeling current, enabling DCM operation and preventing output sinking. Unlike STSR2P, STSR2PM maintains functionality down to sub-13% duty cycles without auto-shutdown, confirmed by electrical characterization at TJ = −40 to +125°C.

Key Specifications

Pinout & Package

STSR2PMCD is housed in an SO-8 package with exposed pad thermal enhancement (R_thj-amb = 160 °C/W on single-layer PCB). Pin functions are electrically isolated between signal (SGLGND) and power (PWRGND) domains to suppress noise coupling into timing logic.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STSR2PCD and MP6908A, STSR2PMCD uniquely combines dual-channel integration, programmable turn-off anticipation, DCM-enabling inhibit logic, and guaranteed operation down to near-zero duty cycles-making it the sole option for high-efficiency, burst-mode-capable forward converters demanding secondary-side timing autonomy.

Availability

STSR2PMCD is available at Aetrix Electronics and suitable for telecom DC-DC bricks, industrial 48 V input PSUs, and server VRM auxiliary rails requiring stable component supply, long-term lifecycle support, and traceable sourcing for production ramp-up.

Supply support for STSR2PMCD 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-grade ICs with vertical manufacturing and rigorous AEC-Q100 qualification processes.

The STSR2P/STSR2PM product line was engineered specifically for high-efficiency forward converter secondary-side synchronous rectification-addressing shoot-through, magnetic reset dependency, and light-load inefficiency challenges in medium-power SMPS.

FAQ

What is the key functional difference between STSR2PMCD and STSR2PCD?

STSR2PMCD maintains gate drive functionality at duty cycles below 13%, while STSR2PCD automatically disables both outputs when duty cycle falls below 13%. This makes STSR2PMCD essential for burst-mode and ultra-light-load operation, whereas STSR2PCD is limited to continuous conduction mode applications with stable minimum duty.

How is OUTGATE2 turn-off anticipation time set on STSR2PMCD?

OUTGATE2 turn-off anticipation (t_ANT2) is set by the voltage applied to pin 3 (SETANT2), which partitions VCC via external resistors. At 0–1/3 VCC, t_ANT2 = 75 ns; at 1/3–2/3 VCC, t_ANT2 = 150 ns; at 2/3–VCC, t_ANT2 = 225 ns. No additional components beyond R1/R2 are required.

Can STSR2PMCD operate without an external clock signal?

No. STSR2PMCD requires an external clock input (CK pin) to synchronize its internal oscillator and generate complementary gate drive signals. The CK signal must meet the 2.6–2.8 V threshold and be free of excessive noise; missing or invalid clock causes loss of output timing and potential shoot-through.

Why are SGLGND and PWRGND separate pins on STSR2PMCD?

SGLGND and PWRGND are physically and electrically isolated to prevent high di/dt current transients on the power ground from injecting noise into timing comparators, the internal oscillator, and the inhibit threshold detector. Layout guidelines require separate traces with no shared copper pour or vias between these domains.