Diodes Incorporated D3Z18BF-7

Overview

D3Z18BF-7 from Diodes Incorporated is a precision 18 V Zener diode in SOD323F package, designed for voltage regulation and reference applications with ±2.2% tolerance (17.56–18.35 V at 5 mA), 400 mW power dissipation on FR-4 PCB, 20 Ω dynamic impedance at 5 mA, and -15.8 mV/°C temperature coefficient. It serves in low-power analog references, overvoltage clamping, and feedback sensing circuits in industrial power supplies.

For engineers reviewing the D3Z18BF-7 datasheet, D3Z18BF-7 pinout, D3Z18BF-7 application, or D3Z18BF-7 equivalent, key selection criteria include Zener voltage accuracy, thermal stability, low leakage (<50 nA at 14.4 V), compact SOD323F footprint, and AEC-Q200 readiness for automotive-grade designs.

Technical Context

This device operates as a two-terminal voltage reference with sharp reverse breakdown at nominal 18 V, specified under pulsed 5 mA test current to minimize self-heating. Its negative temperature coefficient (-15.8 mV/°C) enables predictable drift compensation in stable reference designs.

The SOD323F package delivers low thermal resistance (312.5 °C/W junction-to-ambient) and supports automated placement with matte tin–annealed terminals. Reverse leakage remains ≤50 nA at 14.4 V, ensuring minimal error contribution in high-impedance bias networks.

Key Specifications

Pinout & Package

Package: SOD323F - surface-mount plastic package with cathode band marking, 0.01 g mass, UL 94V-0 rating, and J-STD-020 Level 1 moisture sensitivity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C18LT1G and MMSZ5245B-TP, D3Z18BF-7 delivers tighter voltage tolerance, lower dynamic impedance, and smaller SOD323F footprint-making it optimal for space-constrained, high-stability reference designs where accuracy and thermal performance are critical.

Availability

D3Z18BF-7 is available at Aetrix Electronics and suitable for industrial power supply feedback, automotive sensor reference, overvoltage clamp protection, and portable device battery monitoring requiring stable component supply and long-term sourcing continuity.

Supply support for D3Z18BF-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, manufacturing, and sales operations across Asia, Europe, and the Americas.

The D3Z series targets precision voltage reference and regulation in space-constrained, thermally demanding applications-including automotive, industrial, and consumer electronics-where tight Zener tolerance and environmental compliance are mandatory.

FAQ

What is the maximum continuous power dissipation for D3Z18BF-7 on a standard FR-4 PCB?

D3Z18BF-7 is rated for 400 mW continuous power dissipation when mounted on a standard FR-4 PCB with the recommended pad layout (35 mm × 25 mm). Derating begins above +25°C ambient, reaching zero dissipation at +150°C per the published power derating curve.

Does D3Z18BF-7 meet automotive qualification standards?

D3Z18BF-7 is manufactured in IATF 16949-certified facilities and supports PPAP documentation. While not pre-qualified to AEC-Q200 out-of-box, Diodes Incorporated offers AEC-Q200-compliant variants upon request with full change control-confirm with your local representative for qualified part numbers.

How does the temperature coefficient affect regulation accuracy over temperature?

With a typical temperature coefficient of -15.8 mV/°C, D3Z18BF-7 exhibits a predictable 0.088% per °C drift from nominal 18 V. Over a -40°C to +125°C range, total V_Z shift is approximately ±2.6 V, which must be factored into system-level accuracy budgets for precision references.

Can D3Z18BF-7 be used in place of through-hole Zeners like 1N4746A?

No-D3Z18BF-7 is a surface-mount SOD323F device with different thermal characteristics, mounting requirements, and electrical behavior under pulse conditions. Substitution requires validation of thermal performance, PCB layout, and transient response; it is not a drop-in replacement for through-hole Zeners.