Taiwan Semiconductor Corporation S1AB R5G

Overview

S1AB R5G from Taiwan Semiconductor is a 1 A, 50 V standard surface-mount silicon rectifier diode in DO-214AA (SMB) package, featuring glass-passivated junction, 1.1 V max forward voltage at 1 A, 30 A surge capability, and 5 µA max reverse leakage at 25°C - used in AC/DC input stages of compact SMPS and LED lighting adapters.

For engineers reviewing the S1AB R5G datasheet, S1AB R5G pinout, S1AB R5G application, or S1AB R5G equivalent, key selection criteria include repetitive peak reverse voltage (50 V), thermal resistance (30 °C/W), moisture sensitivity level (MSL 1), RoHS/halogen-free compliance, and SMB footprint compatibility with automated placement.

Technical Context

The S1AB R5G is a single-die, unidirectional standard recovery rectifier optimized for low-cost, high-volume AC/DC front-end conversion. Its glass-passivated junction ensures stable reverse characteristics across temperature, while the DO-214AA (SMB) package supports 1 A continuous forward current with 30 A non-repetitive surge rating per JESD22-A112.

Electrical behavior is defined by a typical junction capacitance of 12 pF at 4 V reverse bias and 1 MHz, and reverse leakage that rises from 5 µA at 25°C to 50 µA at 125°C - critical for standby power and EMI-sensitive lighting converters.

Key Specifications

Pinout & Package

DO-214AA (SMB) surface-mount package with cathode-indicated band; matte tin-plated leads compliant with J-STD-002 solderability and JESD201 Class 2 whisker resistance; UL 94V-0 molding compound; MSL Level 1 per J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M1A and VS-1A50, the S1AB R5G offers identical 50 V/1 A ratings and superior surge margin over M1A, while avoiding MSL Level 2a handling constraints of VS-1A50 - making it optimal for high-throughput, bake-free SMT lines targeting consumer and lighting markets.

Availability

S1AB R5G is available at Aetrix Electronics and suitable for switching mode power supplies, LED lighting adapters, and industrial auxiliary power modules requiring stable component supply, consistent MSL Level 1 handling, and RoHS-compliant procurement.

Supply support for S1AB R5G 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 diodes, MOSFETs, and bipolar transistors since 1979.

The S1AB R5G belongs to TSC's S1x series of standard recovery rectifiers, designed specifically for cost-sensitive, high-volume AC/DC conversion in consumer, lighting, and industrial power applications where reliability, manufacturability, and regulatory compliance are prioritized.

FAQ

What is the maximum junction temperature rating for the S1AB R5G?

The S1AB R5G has a maximum junction temperature (T_J) rating of +150°C, enabling reliable operation in enclosed industrial and lighting environments where ambient temperatures reach 70–85°C. This rating is supported by its 30 °C/W junction-to-lead thermal resistance and DO-214AA package construction. Derating curves in the S1AB R5G datasheet confirm 1 A continuous current is maintainable up to 125°C case temperature.

Is the S1AB R5G suitable for automated SMT assembly without pre-baking?

Yes, the S1AB R5G is rated MSL Level 1 per J-STD-020, meaning it has unlimited floor life and can be placed directly into reflow without baking. Its matte tin-plated leads meet J-STD-002 solderability requirements, and the UL 94V-0 molding compound ensures process stability. This eliminates moisture-related popcorning risk and reduces line downtime in high-volume SMT lines using the S1AB R5G.

How does the reverse leakage current of the S1AB R5G change with temperature?

The S1AB R5G exhibits 5 µA max reverse leakage (I_R) at 25°C and 50 µA max at 125°C under rated reverse voltage. This 10× increase reflects intrinsic silicon behavior and is fully characterized in the datasheet's reverse characteristics curve (Fig.3). For low-standby-power designs, this temperature-dependent leakage must be accounted for in total system quiescent current budgets when using the S1AB R5G.

What is the significance of the "R5G" suffix in S1AB R5G?

The "R5G" suffix in S1AB R5G denotes Taiwan Semiconductor's internal tape-and-reel packaging code: "R5" indicates 3,000 units per reel, and "G" signifies green (halogen-free) molding compound per IEC 61249-2-21. It does not affect electrical specifications - all S1AB variants share identical 50 V VRRM, 1 A IF, and thermal parameters. The base part remains S1AB; R5G specifies packaging and environmental compliance for the S1AB R5G shipment unit.

Can the S1AB R5G replace higher-voltage S1x series diodes like S1JB (600 V) in a design?

No, the S1AB R5G is rated for 50 V VRRM and must not be substituted for higher-voltage variants such as S1JB (600 V) or S1MB (1000 V). Exceeding its 50 V reverse rating risks catastrophic failure during transient events or waveform overshoot. Each S1x variant is electrically distinct; only S1AB R5G, S1BB R5G, etc., share identical package and current ratings but differ strictly in VRRM. Substitution requires full circuit validation for the S1AB R5G.