Diodes Incorporated BZX84C4V3W-7-F

Overview

BZX84C4V3W-7-F from Diodes Incorporated is a 4.3 V, 200 mW surface-mount Zener diode in SOT-323 package, with nominal zener voltage tolerance ±7%, 90 Ω dynamic impedance at 5 mA test current, and maximum reverse leakage of 3.0 µA at 1.0 V, used for precision voltage regulation and reference in low-power analog circuits.

For engineers reviewing the BZX84C4V3W-7-F datasheet, BZX84C4V3W-7-F pinout, BZX84C4V3W-7-F application, or BZX84C4V3W-7-F equivalent, key selection criteria include zener voltage accuracy (4.0–4.6 V), thermal resistance (625 K/W), operating temperature range (−65 to +125 °C), and RoHS-compliant green molding compound construction.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage across load variations. It delivers regulated output at 4.3 V with 5 mA test current and exhibits low dynamic impedance (90 Ω) and tight voltage spread (±0.3 V) under standard conditions.

Its planar die construction ensures repeatable breakdown characteristics and long-term stability. The device is rated for 200 mW power dissipation on FR4 PCB with recommended pad layout, and derates linearly above 25 °C ambient per the published power derating curve.

Key Specifications

Pinout & Package

Package: SOT-323 - ultra-small surface-mount plastic case (2.0 × 1.25 × 0.9 mm), moisture sensitivity level 1, lead-free matte tin plating, UL 94V-0 flammability rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ4685-7-F and BZX84-C4V3,315, BZX84C4V3W-7-F balances RoHS compliance, ultra-compact size, and industrial-grade temperature range while maintaining cost-effective manufacturability in high-volume SMT lines.

Availability

BZX84C4V3W-7-F is available at Aetrix Electronics and suitable for precision voltage reference, overvoltage protection, signal level translation, and low-power monitoring requiring stable component supply across consumer, industrial, and automotive electronics programs.

Supply support for BZX84C4V3W-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, headquartered in Plano, Texas, serving industrial, computing, communications, and consumer markets since 1959.

This part belongs to the BZX84C series of surface-mount Zener diodes designed specifically for space-constrained, low-power voltage regulation and protection in modern SMT-based electronics.

FAQ

What is the maximum reverse voltage before breakdown for BZX84C4V3W-7-F?

The device begins controlled reverse breakdown at its nominal zener voltage of 4.3 V, with guaranteed operation between 4.0 V (min) and 4.6 V (max) at 5 mA test current. Below 4.0 V, reverse leakage remains ≤3.0 µA at 1.0 V, confirming absence of premature conduction.

Can BZX84C4V3W-7-F be used in place of a 3.3 V Zener diode?

No - it is not interchangeable with 3.3 V Zeners such as BZX84C3V3W. Its 4.0–4.6 V regulation range exceeds 3.3 V system thresholds and would cause incorrect biasing or failure to clamp at intended voltage. Use BZX84C3V3W-7-F for 3.3 V applications.

Is thermal derating required for continuous operation at 85 °C ambient?

Yes - at 85 °C ambient, power dissipation must be reduced to 120 mW per the linear derating curve (200 mW at 25 °C, zero at 125 °C). This corresponds to a maximum continuous zener current of ~28 mA at 4.3 V to stay within safe junction temperature limits.

Does BZX84C4V3W-7-F have polarity marking on the package?

Yes - the cathode is marked with a single horizontal bar on the top surface of the SOT-323 package. Pin 1 (anode) is the leftmost terminal when the marking bar is oriented horizontally at the top edge, matching the standard SOT-323 pinout diagram in DS30066 Rev. 15-2.