Nexperia USA Inc. BZB784-C4V3-QX

Overview

BZB784-C4V3-QX from Nexperia is a dual Zener voltage regulator diode in SOT323 (SC-70) package, configured as two cathodes (K1, K2) sharing a common anode (CA), with nominal 4.3 V working voltage, ±5% tolerance, and 350 mW total power dissipation. It delivers low-leakage reverse current (3 µA at VR = 1 V), low differential resistance (410 Ω typ. at IZ = 5 mA), and AEC-Q101 qualification for automotive voltage regulation and ESD protection.

For engineers reviewing the BZB784-C4V3-QX datasheet, BZB784-C4V3-QX pinout, BZB784-C4V3-QX application, or BZB784-C4V3-QX equivalent, this page provides verified electrical parameters, thermal resistance values (Rth(j-a) = 355 K/W for dual-diode operation), junction temperature limit (150 °C), and validated automotive-grade reliability data - all critical for board-level surge suppression and precision biasing in space-constrained ECUs.

Technical Context

This dual-Zener device operates in reverse breakdown to clamp voltages across two independent paths sharing one anode terminal. Its matched 4.3 V nominal Zener voltage enables symmetrical bidirectional clamping or dual-rail reference generation in compact layouts.

Thermal performance is defined for FR4 PCB mounting: Rth(j-sp) = 140 K/W (2 diodes loaded) and Rth(j-a) = 355 K/W, supporting sustained 200 mA forward current and 40 W non-repetitive peak reverse power (tp = 100 µs) under automotive ambient conditions (−55 °C to +150 °C).

Key Specifications

Pinout & Package

SOT323 (SC-70) plastic surface-mount package: 2.0 mm × 1.25 mm × 0.95 mm body, 1.3 mm lead pitch, FR4-compatible footprint with tin-plated copper traces.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5227BS-7-F and BZX84-C4V3, the BZB784-C4V3-QX uniquely combines AEC-Q101 qualification, common-anode dual-Zener integration, and sub-µA leakage at 1 V - enabling single-component bidirectional clamping in thermally constrained automotive domains where reliability and space efficiency are co-primary constraints.

Availability

BZB784-C4V3-QX is available at Aetrix Electronics and suitable for automotive body control modules, infotainment system ESD protection, and ADAS camera reference stability requiring stable component supply, traceable sourcing, and lifecycle continuity assurance.

Supply support for BZB784-C4V3-QX 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

Nexperia is a global semiconductor expert focused on essential efficiency technologies, delivering high-performance logic, discrete, and MOSFET devices optimized for automotive, industrial, and mobile applications.

The BZB784-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode portfolio, engineered specifically for robust voltage regulation and transient suppression in automotive electronic control units where space, reliability, and thermal resilience are critical.

FAQ

What is the maximum continuous forward current rating for BZB784-C4V3-QX?

The absolute maximum forward current (IF) is 200 mA per diode, as specified in Table 5 of the datasheet. This rating applies under free-air conditions at Tamb = 25 °C with proper PCB thermal relief; derating is required above 25 °C ambient per the Rth(j-a) = 355 K/W thermal resistance value for dual-diode operation.

Does BZB784-C4V3-QX support bidirectional transient voltage suppression?

Yes - its common-anode dual-cathode structure allows it to clamp positive transients on either cathode relative to the shared anode, enabling effective bidirectional protection when the anode is tied to a stable reference (e.g., ground or mid-rail). This is confirmed by the pinning diagram and application examples in Section 3 of the datasheet.

How does the temperature coefficient affect regulation accuracy over automotive temperature ranges?

At 4.3 V nominal VZ, the temperature coefficient (SZ) is −1.7 mV/K (typical), meaning output voltage decreases by ~170 mV from −40 °C to +125 °C. This 4.0–4.6 V VZ range remains within specification and is factored into automotive design margins per ISO 16750-2.

Can BZB784-C4V3-QX replace two discrete BZX84-C4V3 diodes in a design?

Yes - it replaces two SOT23 Zeners with identical 4.3 V VZ in a single SOT323 package, reducing PCB area by >40% and eliminating one solder joint. However, the common-anode topology requires circuit redesign to route both protected nodes to separate cathodes while sharing one anode connection point.