Taiwan Semiconductor Corporation 5.0SMDJ48A

Overview

5.0SMDJ48A from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode designed for high-energy surge protection in DC power lines and I/O interfaces. It features a 48 V working standoff voltage, 53.3–58.9 V breakdown voltage at 1 mA, 64.7 A peak pulse current, 77.4 V clamping voltage at rated current, and 5000 W peak pulse power capability per 10/1000 µs waveform.

For engineers reviewing the 5.0SMDJ48A datasheet, 5.0SMDJ48A pinout, 5.0SMDJ48A application, or 5.0SMDJ48A equivalent, key selection criteria include clamping performance under 64.7 A surge, thermal resistance (R_θJL = 16 °C/W), DO-214AB package compatibility with automated SMT assembly, and unidirectional polarity indicated by cathode band.

Technical Context

The 5.0SMDJ48A employs a stacked-die construction in a DO-214AB (SMC) package to achieve 5000 W peak pulse power handling while maintaining fast response (<1.0 ps) and low leakage (<2 µA at 48 V). Its glass-passivated junction ensures stable breakdown characteristics and reliability under repeated transients.

Designed for unidirectional operation, it provides precise overvoltage clamping with a temperature coefficient of breakdown voltage α_VBR = 0.106 mV/°C and operates across –55 °C to +175 °C junction temperature range. Thermal performance is characterized with R_θJA = 61 °C/W on a 16 mm × 16 mm copper pad PCB.

Key Specifications

Pinout & Package

DO-214AB (SMC) package with axial leads; polarity indicated by cathode band. Matte tin-plated terminals meet J-STD-002 solderability requirements. Weight: ~0.300 g.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient voltage suppression applications.

Compared with SMBJ48A and SMCJ48A, the 5.0SMDJ48A delivers superior surge energy handling and lower clamping voltage in the same DO-214AB footprint-critical for protecting 48 V systems against combined lightning and switching transients without increasing board area.

Availability

5.0SMDJ48A is available at Aetrix Electronics and suitable for industrial AC/DC power inputs, telecom DC feeder protection, and automotive body control module designs requiring stable component supply and long-term production continuity.

Supply support for 5.0SMDJ48A 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 Taiwanese semiconductor manufacturer specializing in discrete power devices, including TVS diodes, rectifiers, and MOSFETs.

The 5.0SMDJxxA series was developed to deliver high-power, surface-mount surge protection for 48 V–100 V DC systems in industrial, telecom, and automotive applications-emphasizing reliability, automated assembly compatibility, and JEDEC-compliant thermal performance.

FAQ

What is the maximum clamping voltage of the 5.0SMDJ48A under rated surge conditions?

The 5.0SMDJ48A has a maximum clamping voltage (V_C) of 77.4 V at 64.7 A peak pulse current, measured using the standard 10/1000 µs double-exponential waveform. This value ensures protected circuits remain below critical overvoltage thresholds during full-rated surge events. The 5.0SMDJ48A maintains this clamping performance across its specified junction temperature range of –55 °C to +175 °C.

Is the 5.0SMDJ48A unidirectional or bidirectional, and how is polarity identified?

The 5.0SMDJ48A is a unidirectional TVS diode, intended for DC line protection where reverse voltage is not expected. Polarity is marked by a cathode band on the DO-214AB package body, aligning with the cathode terminal. This marking must be matched to circuit ground reference during PCB layout to ensure correct clamping behavior. The 5.0SMDJ48A does not conduct in reverse bias until breakdown voltage is exceeded.

What is the thermal resistance from junction to lead (R_θJL) for the 5.0SMDJ48A, and why does it matter?

The 5.0SMDJ48A has a typical junction-to-lead thermal resistance (R_θJL) of 16 °C/W, measured with the device mounted on a 16 mm × 16 mm copper pad PCB. This parameter directly impacts steady-state power dissipation capability and transient thermal response. A lower R_θJL allows faster heat transfer from the silicon die to the PCB, improving reliability during repetitive surge events. The 5.0SMDJ48A leverages this to sustain 6.25 W steady-state dissipation at T_L = 75 °C.

Does the 5.0SMDJ48A require moisture preconditioning before reflow soldering?

No, the 5.0SMDJ48A is rated at Moisture Sensitivity Level 1 per J-STD-020, meaning it may be stored indefinitely at ≤30 °C/60% RH without baking or dry-pack requirements. This eliminates pre-reflow bake cycles in manufacturing, reducing process complexity and cost. The 5.0SMDJ48A's glass-passivated chip junction and halogen-free molding compound further support robust reflow performance up to 260 °C peak temperature.

How does the 5.0SMDJ48A compare to the 5.0SMDJ45A in terms of voltage ratings and application suitability?

The 5.0SMDJ48A has a 48 V working standoff voltage (V_WM) and 53.3–58.9 V breakdown range, versus the 5.0SMDJ45A's 45 V V_WM and 50.0–55.3 V V_BR. This makes the 5.0SMDJ48A better suited for nominal 48 V systems where tighter margin above operating voltage is needed. Both share identical 5000 W rating and DO-214AB packaging, but the 5.0SMDJ48A's higher V_WM reduces leakage risk in systems with voltage ripple near 45 V.