STMicroelectronics STTH8R04G

Overview

STTH8R04G from STMicroelectronics is an ultrafast recovery silicon rectifier diode in D²PAK surface-mount package, rated for 400 V repetitive peak reverse voltage, 8 A average forward current (at TC = 145 °C), and 25 ns typical reverse recovery time at IF = 1 A, dIF/dt = −100 A/µs, VR = 30 V. It employs platinum-doped planar technology and is engineered for low-conduction-loss freewheeling and base-drive switching in high-frequency inverters.

For engineers reviewing the STTH8R04G datasheet, STTH8R04G pinout, STTH8R04G application, or STTH8R04G equivalent, key selection criteria include its 25 ns trr (typ), 0.9 V VF (typ) at 25 °C, 175 °C max junction temperature, insulated thermal performance (Rth(j-c) = 2.5 °C/W), and D²PAK footprint compatibility with high-power density PCB layouts.

Technical Context

This diode uses Pt-diffused planar junction technology to achieve soft, fast reverse recovery with S-factor ≥ 0.4 - critical for minimizing EMI and voltage overshoot in hard-switched SMPS and motor drive snubbers. Its low Qrr (typical 35 nC at Tj = 25 °C, VR = 320 V, dIF/dt = 200 A/µs) directly reduces turn-off losses in synchronous rectification stages.

The D²PAK package provides low thermal resistance (Rth(j-c) = 2.5 °C/W) and supports high pulsed currents up to 165 A (IFRM), enabling robust operation under transient overload conditions common in UPS and solar microinverters without derating beyond 145 °C case temperature.

Key Specifications

Pinout & Package

STTH8R04G is housed in a surface-mount D²PAK (TO-263) package with three terminals: Anode (A), Cathode (K), and exposed metal tab (electrically connected to cathode). The package features a single-row 3-pin layout optimized for high-current PCB trace routing and thermal pad soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH8R04G, STTH8R06D trades faster switching for higher voltage headroom and higher conduction loss, while MUR840E offers similar electrical specs but sacrifices thermal efficiency and surface-mount flexibility due to TO-220AC packaging.

Availability

STTH8R04G is available at Aetrix Electronics and suitable for high-frequency inverters, solar microinverters, and industrial SMPS requiring stable component supply, consistent parametric performance, and long-term D²PAK package availability.

Supply support for STTH8R04G 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, MCU, and sensor solutions for automotive, industrial, and consumer markets.

STTH8R04G belongs to ST's ultrafast recovery diode product line, developed specifically for high-efficiency, high-frequency power conversion systems where low Qrr, soft recovery, and thermal robustness are essential.

FAQ

What is the maximum allowable case temperature for continuous 8 A operation?

The STTH8R04G supports 8 A average forward current only when the case temperature (TC) is maintained at ≤145 °C, as specified in Table 2. Exceeding this temperature risks exceeding the 175 °C maximum junction temperature, especially under high ambient or poor heatsinking conditions. Derating curves in Figure 1 confirm that at TC = 125 °C, IF(AV) drops to ~6.5 A.

Is the D²PAK tab electrically isolated?

No - the exposed metal tab on the STTH8R04G D²PAK package is internally connected to the cathode (K) terminal, not insulated. Unlike the TO-220AC Ins variant, this device requires the PCB thermal pad to be routed to the cathode net. Electrical isolation must be achieved externally via insulating thermal pads or dielectric layers if mounting to a grounded heatsink.

How does trr vary with temperature and dIF/dt?

Reverse recovery time decreases with rising junction temperature and increasing dIF/dt. At Tj = 125 °C and dIF/dt = −200 A/µs, trr drops to ~20 ns (Figure 5), improving high-frequency performance but increasing IRM. This inverse relationship is inherent to Pt-doped planar diodes and must be accounted for in EMI filter design.

Can STTH8R04G replace a Schottky diode in 12 V output rectification?

Only if VRRM requirements exceed 40 V and temperature stability is critical: STTH8R04G's VF rises less with temperature than Schottky diodes (0.90 V at 150 °C vs. >0.75 V for most Schottkys), but its trr introduces switching loss absent in Schottky devices. It is unsuitable for <50 kHz applications where Schottky's zero-recovery advantage dominates.