Diodes Incorporated BZX84C43-7

Overview

BZX84C43-7 from Diodes Incorporated is a 43 V, 350 mW surface-mount Zener diode in SOT-23 package, designed for precision voltage regulation and overvoltage protection in low-power analog circuits. It delivers a nominal Zener voltage of 43 V (min 40.0 V, max 46.0 V) at 2.0 mA test current, with 150 Ω dynamic impedance at 2 mA and <0.1 μA reverse leakage at 30.1 V, commonly used in power supply reference and ESD clamp circuits.

For engineers reviewing the BZX84C43-7 datasheet, BZX84C43-7 pinout, BZX84C43-7 application, or BZX84C43-7 equivalent, key selection criteria include Zener voltage tolerance (±6.98%), thermal resistance (357 °C/W), power derating above 25°C, and RoHS-compliant lead-free plating on Alloy 42 leadframe.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable reference voltage under varying load and temperature conditions. Its planar die construction ensures consistent Zener characteristics and low leakage, while the SOT-23 package enables high-density PCB layout and compatibility with reflow soldering.

It exhibits a positive temperature coefficient of +10.0 to +12.0 mV/°C, enabling predictable drift compensation in temperature-sensitive references. The device is rated for operation from –65°C to +150°C and supports pulsed Zener current up to 50 mA per derating curve.

Key Specifications

Pinout & Package

Package: SOT-23 - surface-mount plastic case (UL 94V-0), 0.008 g weight, moisture sensitivity level 1, matte tin-plated Alloy 42 leadframe.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener regulation applications.

Compared with MMBZ43VCW and BZX84-C43,115, the BZX84C43-7 offers superior power handling (350 mW vs. 200 mW) and tighter thermal resistance (357 °C/W), making it preferred for sustained-clamp and industrial-grade reference applications where reliability under thermal stress is critical.

Availability

BZX84C43-7 is available at Aetrix Electronics and suitable for power supply reference, overvoltage clamp, and low-power sensor excitation applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for BZX84C43-7 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design and manufacturing operations across Asia and the Americas.

The BZX84 series belongs to Diodes' precision Zener diode product line, engineered specifically for voltage regulation, reference, and protection in space-constrained, cost-sensitive consumer and industrial electronics.

FAQ

What is the maximum Zener current the BZX84C43-7 can handle continuously?

The BZX84C43-7 supports a maximum continuous Zener current of approximately 8.1 mA at 25°C ambient, calculated from its 350 mW power rating divided by 43 V. Above 25°C, current must be reduced per the derating curve-e.g., to ~5.7 mA at 70°C ambient-to avoid exceeding junction temperature limits.

Is the BZX84C43-7 suitable for use in automotive applications?

The BZX84C43-7 is not AEC-Q101 qualified. While it operates across –65°C to +150°C and meets RoHS requirements, automotive-grade use requires validation against AEC-Q101 stress tests. For such applications, consider the AEC-Q101-qualified NXP BZX84-C43,115 or ON Semiconductor's 1SMA4743.

How does the temperature coefficient affect regulation accuracy over –40°C to +85°C?

With a +10.0 to +12.0 mV/°C temperature coefficient, the BZX84C43-7's Zener voltage increases by ~1.25 V over a 125°C span. At 85°C, V_Z rises to ~44.25–44.5 V, introducing ±2.9% deviation from nominal-acceptable for non-critical references but requiring compensation in precision systems.

Can the BZX84C43-7 replace a 43 V Zener in a circuit originally using through-hole DO-35?

Yes, provided PCB layout accommodates SOT-23 pad dimensions and thermal design accounts for lower power dissipation (350 mW vs. typical DO-35's 500–1000 mW). Derating must be applied, and mechanical stress on leads eliminated-no direct mechanical interchangeability exists due to differing mounting methods and thermal paths.