Taiwan Semiconductor Corporation SMA4F36AH

Overview

SMA4F36AH from Taiwan Semiconductor is a unidirectional, AEC-Q101-qualified transient voltage suppressor diode in Thin SMA package, with 36 V working stand-off voltage (VWM), 40.2–44.5 V breakdown voltage (VBR) at 1 mA, 58.4 V clamping voltage (VC) at 6.8 A peak pulse current, and 400 W peak pulse power rating for 10/1000 µs waveform - used for overvoltage protection in automotive BLDC motor drives and battery management systems.

For engineers reviewing the SMA4F36AH datasheet, SMA4F36AH pinout, SMA4F36AH application, or SMA4F36AH equivalent, key selection considerations include its unidirectional polarity, 175 °C maximum junction temperature, 20 °C/W junction-to-lead thermal resistance, 6.8 A peak impulse current rating, and compliance with JESD201 Class 2 whisker testing and RoHS/halogen-free requirements.

Technical Context

The SMA4F36AH operates as a unidirectional TVS diode with glass-passivated junction, designed to clamp transient overvoltages above its breakdown threshold while maintaining low leakage (<1 µA at 36 V). Its thermal design supports operation up to 175 °C junction temperature with R_θJL = 20 °C/W on a 5 mm × 5 mm copper pad PCB.

It delivers 400 W non-repetitive peak pulse power per 10/1000 µs waveform, with clamping performance validated at 6.8 A IPPM yielding 58.4 V VC - enabling robust surge immunity in automotive-grade power electronics where fast response and stable VBR temperature coefficient (0.095 %/°C) are critical.

Key Specifications

Pinout & Package

Thin SMA package: surface-mount, single-die, unidirectional configuration with cathode band marking. Dimensions conform to standard Thin SMA outline; terminals are matte tin-plated for J-STD-002 solderability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ36A and SMBJ36A, the SMA4F36AH uniquely combines AEC-Q101 qualification, Thin SMA form factor, and 20 °C/W R_θJL - making it optimal for space-constrained automotive modules requiring validated reliability and efficient thermal transfer without layout change.

Availability

SMA4F36AH is available at Aetrix Electronics and suitable for automotive BLDC motor drives, battery management systems, and LED lighting applications requiring stable component supply, AEC-Q101 compliance, and consistent Thin SMA packaging.

Supply support for SMA4F36AH 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 automotive, industrial, and consumer markets since 1979.

The SMA4FxxAH series belongs to TSC's AEC-Q101-qualified TVS diode product line, engineered specifically for high-reliability transient suppression in automotive power electronics where thermal stability, low leakage, and precise VBR tolerance are mandatory.

FAQ

What is the breakdown voltage range of the SMA4F36AH?

The SMA4F36AH has a guaranteed breakdown voltage (VBR) range of 40.2 V to 44.5 V at a test current (IT) of 1 mA, measured per JEDEC standards. This range ensures consistent clamping behavior across production lots and supports accurate system-level surge margin calculation. The SMA4F36AH's specified VBR tolerance directly enables reliable protection design for 36 V nominal battery systems.

Is the SMA4F36AH suitable for automotive applications?

Yes, the SMA4F36AH is AEC-Q101 qualified and rated for operation from –55 °C to +175 °C junction temperature, making it suitable for under-hood and cabin automotive applications. It meets JESD201 Class 2 whisker resistance and J-STD-020 MSL Level 1, confirming robustness against thermal cycling and moisture sensitivity - all verified per the official Taiwan Semiconductor qualification report for SMA4F36AH.

What is the clamping voltage of the SMA4F36AH at its rated peak pulse current?

The SMA4F36AH exhibits a maximum clamping voltage (VC) of 58.4 V at a peak pulse current (IPPM) of 6.8 A with a 10/1000 µs waveform. This value is measured under standardized conditions and defines the upper voltage limit imposed on protected circuitry during surge events. Designers use this VC value alongside system voltage rails to verify safe operating margins for downstream components in the SMA4F36AH-protected path.

Does the SMA4F36AH have unidirectional or bidirectional polarity?

The SMA4F36AH is a unidirectional TVS diode, indicated by its single cathode band marking and specified electrical parameters (e.g., forward voltage VF = 3.5 V at 25 A). It conducts only during reverse-biased overvoltage events and must be oriented with cathode toward the higher-potential rail. Bidirectional variants (e.g., SMA4F36AY) are separate part numbers and are not interchangeable with the SMA4F36AH.

What is the thermal resistance from junction to lead (RθJL) for the SMA4F36AH?

The SMA4F36AH has a typical junction-to-lead thermal resistance (RθJL) of 20 °C/W when mounted on a 5 mm × 5 mm copper pad PCB, per Taiwan Semiconductor's thermal characterization data. This parameter quantifies how effectively heat transfers from the silicon die to the PCB leads and informs thermal design decisions such as copper area allocation and adjacent component placement to maintain TJ ≤ 175 °C under sustained power dissipation.