Taiwan Semiconductor Corporation SA24AH

Overview

SA24AH from Taiwan Semiconductor is a unidirectional AEC-Q101 qualified transient voltage suppressor (TVS) diode in DO-204AC (DO-15) package, designed for automotive and industrial overvoltage protection. It features 24 V working stand-off voltage (VWM), 26.7–32.6 V breakdown voltage (VBR @ 1 mA), 42.1 V maximum clamping voltage (VC) at 12.0 A peak pulse current, and 500 W surge capability per 10/1000 μs waveform.

For engineers reviewing the SA24AH datasheet, SA24AH pinout, SA24AH application, or SA24AH equivalent, this device is selected for robust ESD and EFT immunity in 12 V automotive subsystems, DC power rail protection in industrial controls, and inductive load switching circuits where fast response (<1.0 ps), low leakage (<1 μA @ 24 V), and high junction temperature tolerance (−55°C to +175°C) are critical.

Technical Context

The SA24AH operates as a unidirectional avalanche diode, triggering when reverse voltage exceeds its specified VBR range (26.7–32.6 V). Its clamping action limits transient energy to ≤42.1 V at 12.0 A, enabling protection of downstream 24 V-rated ICs and microcontrollers. The device exhibits <1.0 ps response time from 0 V to VBR and maintains <1 μA reverse leakage above 10 V.

Rated for 500 W peak pulse power (10/1000 μs), it derates linearly above 25°C ambient and supports steady-state dissipation of 3 W at lead temperature TL = 75°C. Its DO-204AC package meets UL 94V-0, JESD201 Class 2 whisker resistance, and RoHS/halogen-free compliance per IEC 61249-2-21.

Key Specifications

Pinout & Package

SA24AH is a two-terminal unidirectional TVS diode in DO-204AC (DO-15) package. Cathode is marked by a band on the body; anode is unmarked. Leads are pure tin-plated and solderable per J-STD-002. Polarity must be observed during PCB placement to ensure correct clamping direction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ24A and 1.5KE24A, SA24AH delivers automotive-grade reliability via AEC-Q101 qualification, lower leakage (<1 μA), and identical 500 W surge rating - making it the sole choice for safety-critical 24 V automotive ECUs where long-term parametric stability and qualification traceability are mandatory.

Availability

SA24AH is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC I/O modules, and smart lighting power systems requiring stable component supply with full AEC-Q101 documentation and lot-level traceability.

Supply support for SA24AH 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 semiconductor manufacturer specializing in discrete power devices, TVS diodes, rectifiers, and MOSFETs, with global distribution and AEC-Q101 certified product lines.

The SA Series was developed specifically for automotive and harsh-environment industrial transient suppression, emphasizing high surge robustness, low leakage, and qualification-grade reliability in axial-leaded packages.

FAQ

What does the "H" suffix in SA24AH signify?

The "H" suffix in SA24AH indicates full AEC-Q101 qualification per Rev D test plan, covering stress tests including high-temperature reverse bias (HTRB), temperature cycling (TC), and ESD (HBM/MM). This certification confirms SA24AH's suitability for automotive under-hood and chassis applications where reliability under thermal and electrical stress is mandatory - unlike non-H variants such as SA24A.

Is SA24AH unidirectional or bidirectional?

SA24AH is a unidirectional TVS diode, as confirmed by its marking diagram (cathode band), specification table (VBR listed for unidirectional only), and absence of bidirectional parameters in its datasheet section. It protects against positive transients on the cathode side relative to anode (ground), and must not be used for AC or bipolar surge scenarios without external circuitry.

What is the maximum clamping voltage of SA24AH and at what current is it measured?

The maximum clamping voltage of SA24AH is 42.1 V, measured at 12.0 A peak pulse current (IPPM) under the standardized 10/1000 μs double-exponential surge waveform. This value is guaranteed across temperature and process variation, and defines the upper voltage limit imposed on protected circuitry during worst-case transients.

Can SA24AH replace SA24A in an existing design?

Yes, SA24AH is a direct replacement for SA24A in terms of electrical parameters and DO-204AC packaging, with identical VWM (24 V), VBR (26.7–32.6 V), VC (42.1 V), and IPPM (12.0 A). The only difference is AEC-Q101 qualification - SA24AH adds automotive-grade reliability validation without altering schematic or layout.

What is the junction-to-ambient thermal resistance (RθJA) for SA24AH?

RθJA is not specified for SA24AH in the provided documentation. Thermal performance is characterized via derating curves (Fig.2) and steady-state power dissipation (PD = 3 W at TL = 75°C with 9.5 mm lead length). For board-level thermal modeling, users must rely on JEDEC JESD51-2 compliant measurements or TSC's application notes - RθJA varies significantly with PCB copper area and mounting conditions.