Taiwan Semiconductor Corporation S2DAF-T

Overview

S2DAF-T from Taiwan Semiconductor is a 2A, 200V standard surface-mount silicon rectifier diode in SMAF package, featuring glass passivated junction, 50A surge rating (8.3ms), 0.95V max forward voltage at 2A/25°C, and 5µA max reverse leakage at 25°C - used in DC-DC converters and switching-mode power supplies.

For engineers reviewing the S2DAF-T datasheet, S2DAF-T pinout, S2DAF-T application, or S2DAF-T equivalent, key selection criteria include repetitive peak reverse voltage (200V), thermal resistance (R_θJL = 15°C/W), moisture sensitivity level (MSL 1), RoHS/halogen-free compliance, and tape-and-reel packaging (7,500 pcs).

Technical Context

The S2DAF-T is a single-die, general-purpose silicon rectifier optimized for high-efficiency AC-to-DC conversion in compact power stages. Its glass-passivated junction ensures stable reverse characteristics and low IR across temperature, while the SMAF package enables automated placement and meets UL 94V-0 flammability requirements.

Thermal performance is characterized with R_θJA = 89°C/W on a 5mm × 5mm Cu pad PCB, supporting continuous 2A operation up to 125°C ambient when derated per Fig.1. Reverse recovery behavior is not specified; it is intended for non-critical switching applications where soft recovery is not required.

Key Specifications

Pinout & Package

Package: SMAF (Surface Mount Axial Flat), molded plastic case with matte tin-plated leads, polarity indicated by cathode band, weight ≈ 0.035 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STPS2H100S and SB220-E3/52, the S2DAF-T offers superior reverse voltage margin and thermal stability for primary-side or universal-input applications, while trading higher V_F for ruggedness, lower leakage, and extended temperature capability up to 150°C.

Availability

S2DAF-T is available at Aetrix Electronics and suitable for DC–DC converters, switching mode inverters, and general-purpose AC/DC power supplies requiring stable component supply, MSL-1 assembly readiness, and long-term industrial availability.

Supply support for S2DAF-T 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, serving global power, automotive, and industrial markets since 1979.

The S2DAF-T belongs to TSC's S2xAx-T family of standard rectifiers designed for cost-sensitive, high-reliability AC/DC front-end and DC–DC secondary-side applications where ruggedness, consistency, and regulatory compliance are critical.

FAQ

What is the maximum repetitive peak reverse voltage rating for S2DAF-T?

The S2DAF-T has a maximum repetitive peak reverse voltage (V_RRM) of 200 V, verified per Taiwan Semiconductor's B2103 datasheet. This rating defines the highest reverse-biased voltage the device can block repeatedly without breakdown. It is critical for selecting appropriate safety margins in bridge rectifier or flyback clamp circuits. Exceeding 200 V risks irreversible avalanche failure. The S2DAF-T is the lowest-voltage variant in the S2xAx-T series, with higher-voltage versions (e.g., S2MAF-T) rated up to 1000 V.

Does S2DAF-T have a specified reverse recovery time (t_rr)?

No, the S2DAF-T datasheet does not specify reverse recovery time (t_rr). It is a standard (non-fast or ultrafast) silicon rectifier, not optimized for high-frequency switching. Its electrical specifications emphasize low leakage and stable V_F, not soft recovery. For applications requiring t_rr < 500 ns, a fast recovery or Schottky alternative should be evaluated. The S2DAF-T is best suited for line-frequency or moderate-frequency (<100 kHz) rectification where recovery losses are secondary to conduction and leakage performance.

What is the thermal resistance from junction to ambient (R_θJA) for S2DAF-T?

The S2DAF-T has a junction-to-ambient thermal resistance (R_θJA) of 89°C/W, measured on a standard 5 mm × 5 mm copper pad test board per JEDEC standards. This value assumes natural convection and no additional heatsinking. Designers must apply this R_θJA with actual power dissipation (P_D = V_F × I_F) to estimate junction temperature rise above ambient. For sustained 2 A operation at elevated ambient, PCB copper area and airflow should be validated against the derating curve in Figure 1 of the S2DAF-T datasheet.

Is S2DAF-T suitable for lead-free reflow soldering?

Yes, the S2DAF-T is qualified for lead-free reflow soldering. Its matte tin-plated leads meet J-STD-002 solderability requirements, and its MSL Level 1 rating per J-STD-020 means it can be exposed to ambient conditions indefinitely without baking. The device supports peak reflow temperatures up to 260°C (per JEDEC J-STD-020), making it compatible with standard Pb-free SAC305 profiles. No special handling or preconditioning is required prior to assembly.

What marking code appears on the S2DAF-T device body?

The S2DAF-T is marked "S2DAF" on its body, as confirmed in the Absolute Maximum Ratings table of the Taiwan Semiconductor datasheet (Version B2103). This 5-character code identifies the specific 200V variant within the S2xAx-T family. The "F" suffix denotes the SMAF package, and the "-T" in the ordering code indicates tape-and-reel packaging (7,500 units per reel). No date code, factory code, or green compound indicator is part of the base marking for S2DAF-T.