Diodes Incorporated BZX84C4V3-7-F

Overview

BZX84C4V3-7-F from Diodes Incorporated is a 4.3 V, 5 mA nominal Zener voltage regulator diode in SOT23 package, rated for 350 mW power dissipation at ambient temperature, with 90 Ω maximum Zener impedance at test current and ±0.3 V tolerance (4.0–4.6 V), used for precision voltage reference and overvoltage protection in low-power analog circuits.

For engineers reviewing the BZX84C4V3-7-F datasheet, BZX84C4V3-7-F pinout, BZX84C4V3-7-F application, or BZX84C4V3-7-F equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (357 °C/W), reverse leakage (≤3.0 µA at 1.0 V), temperature coefficient (−3.5 mV/°C), and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This Zener diode operates in reverse breakdown to maintain stable voltage across load variations and supply fluctuations. Its planar die construction ensures consistent breakdown characteristics and low dynamic impedance (90 Ω at 5 mA), enabling accurate regulation in feedback paths and reference nodes.

The device exhibits a negative temperature coefficient of −3.5 mV/°C, indicating predictable voltage drift with temperature-critical for compensated references-and is qualified to AEC-Q101, confirming suitability for automotive electronics where thermal cycling and long-term stability are essential.

Key Specifications

Pinout & Package

Package: SOT23 - three-terminal, surface-mount plastic package with matte tin-plated alloy 42 leadframe; moisture sensitivity level 1 per J-STD-020; weight ≈ 0.008 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5225BS-7-F and BZX84-C4V3,315, BZX84C4V3-7-F offers superior thermal performance (350 mW vs. 200/250 mW), tighter voltage tolerance (±0.3 V vs. ±0.18 V/±0.23 V), and AEC-Q101 validation-making it the preferred choice for automotive and industrial voltage reference designs demanding long-term stability.

Availability

BZX84C4V3-7-F is available at Aetrix Electronics and suitable for automotive sensor biasing, USB port overvoltage protection, and industrial PLC input conditioning requiring stable component supply, full traceability, and lifecycle continuity.

Supply support for BZX84C4V3-7-F 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, specializing in high-reliability components for automotive, industrial, and computing markets.

BZX84C series belongs to Diodes' standard Zener diode product line, engineered for precision voltage regulation and transient suppression in space-constrained, thermally demanding applications.

FAQ

What is the maximum reverse voltage this diode can withstand before breakdown?

The BZX84C4V3-7-F has a nominal Zener voltage of 4.3 V with a guaranteed range of 4.0–4.6 V at 5 mA test current. It begins controlled reverse breakdown within this band and is not rated for sustained operation above 4.6 V without exceeding power limits. Absolute maximum reverse voltage is not specified separately-the device is designed to operate *at* its Zener voltage, not above it.

Is this part suitable for use in automotive under-hood applications?

Yes. BZX84C4V3-7-F is explicitly qualified to AEC-Q101 standards and rated for operating temperatures from −65°C to +150°C. Its planar die construction, green molding compound, and 350 mW ambient-rated power dissipation make it appropriate for engine control units, sensor modules, and body electronics exposed to under-hood thermal stress.

How does the −3.5 mV/°C temperature coefficient affect circuit performance?

The negative temperature coefficient means the Zener voltage decreases by approximately 3.5 mV per degree Celsius rise in junction temperature. In a 4.3 V reference, this yields ~0.08% drift per °C-critical for high-accuracy applications. Designers compensate by pairing with positive-TC components or using it in temperature-stable environments like sealed modules.

Can this diode replace a 4.7 V Zener in an existing design?

No-BZX84C4V3-7-F is specifically rated for 4.3 V (4.0–4.6 V), while BZX84C4V7-7-F provides 4.7 V (4.4–5.0 V). Substituting alters regulation level by ≥0.4 V, potentially causing overbiasing or undervoltage in sensitive analog stages. Always match nominal Zener voltage and verify tolerance overlap before replacement.