STMicroelectronics STTH4R02SY

Overview

STTH4R02SY from STMicroelectronics is an AEC-Q101-qualified ultrafast recovery silicon diode in SMC package, rated for 200 V repetitive peak reverse voltage, 4 A average forward current, and 16 ns typical reverse recovery time at 125 °C. It delivers low conduction losses (VF = 0.76 V typ. at 150 °C, 4 A) and negligible switching losses, making it suitable for freewheeling and polarity protection in automotive DC/DC converters and motor control inverters.

For engineers reviewing the STTH4R02SY datasheet, STTH4R02SY pinout, STTH4R02SY application, or STTH4R02SY equivalent, key selection criteria include its 175 °C maximum junction temperature, 70 A non-repetitive surge rating, AEC-Q101 qualification status, and thermal resistance of 20 °C/W (junction-to-lead), critical for high-reliability under-hood power designs.

Technical Context

This diode employs ST's planar platinum-doped technology to achieve ultrafast soft recovery with trr = 16 ns (typ.) at IF = 1 A, dIF/dt = −100 A/µs, VR = 30 V, and Qrr = 60 nC at Tj = 125 °C. Its low VF (0.76 V typ. at 150 °C, 4 A) and high Tj(max) = 175 °C enable efficient operation in thermally constrained automotive environments.

The device supports high-frequency switching up to ~1 MHz in low-voltage (<200 V) topologies, with IR ≤ 2 µA at 125 °C and VR = VRRM. Its SMC package provides a thermal resistance of 20 °C/W (junction-to-lead), enabling direct PCB copper heatsinking without external mounting hardware.

Key Specifications

Pinout & Package

STTH4R02SY is housed in an SMC (DO-214AB) surface-mount package with two terminals: Cathode (K) and Anode (A). The package features a gull-wing leadform optimized for automated assembly and thermal conduction through the leads into PCB copper.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultrafast recovery diode applications.

Compared with STTH4R02UY and STTH4R02BY-TR, STTH4R02SY offers balanced thermal performance (Rth(j-l) = 20 °C/W) and SMC mechanical robustness-ideal for automated assembly in mid-power automotive modules where both thermal and layout constraints apply.

Availability

STTH4R02SY is available at Aetrix Electronics and suitable for automotive DC/DC converters, engine control unit (ECU) power supplies, and electric power steering (EPS) inverters requiring stable component supply, AEC-Q101 compliance, and consistent ultrafast recovery performance.

Supply support for STTH4R02SY 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 analog, power, microcontroller, and sensor solutions for automotive, industrial, and consumer markets.

STTH4R02SY belongs to ST's automotive-qualified ultrafast diode product line, engineered specifically for high-reliability power conversion in harsh-temperature, high-transient automotive environments.

FAQ

Is STTH4R02SY pin-compatible with other STTH4R02 variants?

No-STTH4R02SY uses the SMC (DO-214AB) package with gull-wing leads, while STTH4R02UY (SMB/DO-214AA) and STTH4R02BY-TR (DPAK/TO-252) have different footprints and thermal interfaces. PCB layout and thermal design must be re-validated for each variant.

What is the maximum allowable PCB copper area for optimal thermal performance of STTH4R02SY?

Per Figure 13 in the datasheet, Rth(j-a) drops from ~65 °C/W (no copper) to ~35 °C/W with 10 cm² of 35 µm copper on FR4. For 4 A continuous operation, ≥5 cm² per lead is recommended to maintain Tj < 150 °C at 85 °C ambient.

Does STTH4R02SY require a snubber circuit in typical automotive switching applications?

Not typically-its soft ultrafast recovery (trr = 16 ns, low IRM and Qrr) minimizes voltage overshoot in buck, flyback, and inverter freewheeling paths operating below 200 kHz. Snubbers may still be needed for >500 kHz designs or layouts with high parasitic inductance.

How does STTH4R02SY's AEC-Q101 qualification differ from standard industrial diodes?

AEC-Q101 certification requires extended stress testing-including 1000-hour HTOL at 175 °C, 1000-cycle temperature cycling (−40 °C to +150 °C), and mechanical shock-beyond JEDEC JESD22 standards. This validates long-term reliability in automotive under-hood environments.