Taiwan Semiconductor Corporation SS120

Overview

SS120 from Taiwan Semiconductor is a 1 A, 200 V Schottky barrier surface-mount rectifier in DO-214AC (SMA) package, featuring low forward voltage (0.95 V max at 1 A, 25°C), high surge capability (40 A IFSM), and junction temperature range of –55°C to +150°C; used in SMPS output rectification where efficiency and thermal robustness are critical.

For engineers reviewing the SS120 datasheet, SS120 pinout, SS120 application, or SS120 equivalent, key selection considerations include its 28°C/W junction-to-lead thermal resistance, 10,000 V/µs dV/dt rating, RoHS/halogen-free compliance, and suitability for automated SMT assembly with J-STD-020 Level 1 moisture sensitivity.

Technical Context

The SS120 employs a single-die Schottky structure optimized for low conduction loss and fast switching, eliminating minority-carrier recovery delay. Its guard ring design enhances ruggedness against transient overvoltage events without requiring external snubbers.

Thermal performance is characterized on a 5 mm × 5 mm copper pad PCB per JEDEC standards, yielding R_θJA = 88°C/W and R_θJL = 28°C/W - enabling reliable operation at full rated current up to 125°C ambient when properly mounted.

Key Specifications

Pinout & Package

Package: DO-214AC (SMA), surface-mount plastic case with matte tin-plated leads, cathode indicated by band. Weight: 0.066 g. Meets UL 94V-0 and JESD201 Class 2 whisker requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SS120H and VS-1EWH02-M3/5A, the SS120 offers balanced trade-offs: superior high-temperature leakage performance (2 mA max @ 125°C), robust surge rating (40 A), and proven manufacturability in J-STD-020 Level 1 SMT lines - making it optimal for cost-sensitive, thermally demanding industrial and lighting applications.

Availability

SS120 is available at Aetrix Electronics and suitable for switching mode power supplies, LED lighting drivers, and USB-C adapters requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for SS120 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 management and protection markets since 1979.

The SS120 belongs to TSC's SMA-packaged Schottky rectifier product line, engineered specifically for high-efficiency, high-reliability secondary-side rectification in space-constrained AC-DC and DC-DC converters.

FAQ

What is the maximum junction temperature rating for the SS120?

The SS120 has a maximum junction temperature (T_J) of +150°C, verified per TSC's datasheet revision C2305. This rating enables operation in thermally demanding environments such as enclosed LED drivers or industrial DC-DC converters. Derating curves in the SS120 datasheet confirm sustained 1 A forward current capability up to 125°C ambient when mounted on a standard 5 mm × 5 mm Cu pad.

Does the SS120 have a guard ring, and what function does it serve?

Yes, the SS120 incorporates a guard ring structure explicitly cited in its features list. This design element prevents premature edge breakdown under high dv/dt or transient overvoltage conditions - enhancing reliability in flyback and resonant converter topologies where voltage overshoot is common. The guard ring contributes directly to the SS120's 10,000 V/µs dV/dt rating.

Is the SS120 suitable for automated SMT assembly, and what is its moisture sensitivity level?

Yes, the SS120 is designed for automated placement and carries J-STD-020 Moisture Sensitivity Level 1 - meaning it can be stored indefinitely at ≤30°C/60% RH and placed directly onto reflow lines without baking. Its matte tin-plated leads ensure solderability per J-STD-002, and the DO-214AC (SMA) package geometry supports high-yield pick-and-place accuracy in high-volume adapter manufacturing.

What is the typical forward voltage of the SS120 at elevated temperature?

At 1 A forward current and 125°C junction temperature, the SS120 exhibits a typical forward voltage (V_F) of 0.65 V, with a maximum of 0.85 V. This reduction versus room-temperature V_F (0.82 V typ) reflects the negative temperature coefficient of Schottky diodes and supports stable thermal behavior in high-ambient applications like enclosed power supplies.

How does the SS120's thermal resistance compare between junction-to-lead and junction-to-ambient?

The SS120 has R_θJL = 28°C/W and R_θJA = 88°C/W (measured on 5 mm × 5 mm Cu pad). This 3.1× difference highlights the importance of thermal via placement: most heat flows through the leads into the PCB, not through air. Optimizing copper area and thermal vias under the cathode/anode pads significantly improves real-world thermal performance beyond the R_θJA baseline.