Taiwan Semiconductor Corporation SFAF808G

Overview

SFAF808G from Taiwan Semiconductor is a single-die, super fast recovery rectifier diode in ITO-220AC package, rated for 600 V repetitive peak reverse voltage (V_RRM), 8 A average forward current (I_F), and 125 A non-repetitive surge current (I_FSM). It delivers 1.700 V typical forward voltage at 8 A and 25°C, with 35 ns reverse recovery time (t_rr) and 60 pF junction capacitance - optimized for high-frequency switching power supplies.

For engineers reviewing the SFAF808G datasheet, SFAF808G pinout, SFAF808G application, or SFAF808G equivalent, key selection criteria include its 600 V V_RRM, low t_rr for reduced switching loss, thermal resistance of 4°C/W, AEC-Q101 qualification option (SFAF808GH), and compatibility with DC-DC converters requiring fast, reliable freewheeling or output rectification.

Technical Context

The SFAF808G employs a glass-passivated silicon junction to achieve stable high-voltage blocking and fast carrier recombination. Its 35 ns reverse recovery time enables operation in high-frequency SMPS topologies up to several hundred kHz without excessive switching loss or EMI generation.

Thermally, the ITO-220AC package provides 4°C/W junction-to-case resistance, supporting continuous 8 A conduction at case temperatures ≤100°C. The device operates across –55°C to +150°C junction temperature range and meets UL 94V-0 flammability and JESD201 Class 2 whisker resistance requirements.

Key Specifications

Pinout & Package

Package: ITO-220AC - insulated thermoplastic outline with single anode/cathode configuration, matte tin-plated leads, UL 94V-0 molding compound, and 0.56 N·m maximum mounting torque.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH8R06DJF and IXYS MUR860E, the SFAF808G offers balanced performance: lower V_F than MUR860E and better automotive readiness than STTH8R06DJF, making it optimal for industrial and Tier-1 automotive auxiliary power supplies where thermal robustness and medium-speed recovery are prioritized.

Availability

SFAF808G is available at Aetrix Electronics and suitable for DC-DC converters, switching mode inverters, and freewheeling applications requiring stable component supply, high surge tolerance, and long-term industrial lifecycle support.

Supply support for SFAF808G 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

Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, specializing in power rectifiers, TVS devices, and MOSFETs for industrial and automotive markets.

The SFAF801G–SFAF808G series was designed specifically for high-efficiency, high-reliability switching power conversion - emphasizing fast recovery, low forward drop, and rugged packaging for demanding 100–300 W power stage applications.

FAQ

What is the maximum junction temperature rating for the SFAF808G?

The SFAF808G has a maximum junction temperature (T_J) of +150°C and a minimum of –55°C. This wide operating range supports deployment in harsh environments such as industrial motor drives and automotive engine compartments. Derating curves in the datasheet specify that full 8 A current is sustainable only up to 100°C case temperature; above that, linear derating applies. Thermal design must account for the 4°C/W R_θJC to avoid exceeding the SFAF808G's TJ limit.

Is the SFAF808G pin-compatible with other ITO-220AC rectifiers like the STTH8R06DJF?

Yes - the SFAF808G uses the industry-standard ITO-220AC package with identical mechanical footprint, lead pitch, and tab orientation as STTH8R06DJF and MUR860E. All three share the same anode-tab/cathode-lead pinout and mounting hole pattern. However, electrical characteristics differ significantly: SFAF808G offers lower V_F (1.700 V) than STTH8R06DJF (1.85 V) and faster t_rr than MUR860E (35 ns vs. 60 ns), so layout reuse is possible but performance validation is required.

Does the SFAF808G meet automotive qualification standards?

The base SFAF808G is not AEC-Q101 qualified, but the SFAF808GH variant is explicitly certified to AEC-Q101. Both share identical electrical and thermal specifications; the "H" suffix denotes additional stress testing including temperature cycling, high-temperature reverse bias, and unbiased high-humidity operating life. For automotive applications such as body control modules or ADAS power supplies, SFAF808GH must be specified - the SFAF808G alone does not satisfy automotive reliability requirements.

What is the reverse recovery charge (Q_rr) of the SFAF808G, and how is it derived?

The datasheet does not list Q_rr directly, but it can be estimated using t_rr = 35 ns and I_RR ≈ 0.25 A (per test condition in Fig.6). Assuming triangular reverse current waveform, Q_rr ≈ 0.5 × I_RR × t_rr ≈ 4.4 nC. This low Q_rr contributes to reduced switching loss and EMI in high-frequency converters. For precise Q_rr values under specific conditions (e.g., I_F = 8 A, di/dt = 100 A/µs), refer to the SFAF808G's characterization curves or request TSC's SPICE model.

How does the SFAF808G's junction capacitance affect EMI in high-speed power supplies?

The SFAF808G exhibits 60 pF junction capacitance at 1 MHz and 4 V reverse bias - 33% lower than the 90 pF of lower-voltage variants (SFAF801G–SFAF804G). This reduced C_J limits high-frequency displacement current during switching transitions, lowering common-mode noise injection into PCB traces and nearby circuitry. In 300 kHz LLC resonant converters, this translates to measurable reduction in conducted EMI above 30 MHz, easing EMC filter design and certification effort for the SFAF808G-based power stage.