Diodes Incorporated DDZX39F-13

Overview

DDZX39F-13 from Diodes Incorporated is a surface-mount precision Zener diode in SOT23 package, rated for 39 V nominal zener voltage (38.02–39.98 V at 5 mA), 300 mW power dissipation on FR-4 PCB, and 85 Ω maximum zener impedance at test current. It delivers tight voltage tolerance, low leakage (<0.05 µA at 30 V), and AEC-Q101 qualification-used for voltage regulation and reference in automotive power management circuits.

For engineers reviewing the DDZX39F-13 datasheet, DDZX39F-13 pinout, DDZX39F-13 application, or DDZX39F-13 equivalent, this page provides verified electrical parameters, thermal derating behavior, SOT23 terminal mapping, automotive-grade reliability data, and direct alternatives with documented voltage and impedance differences.

Technical Context

This Zener diode operates in reverse breakdown mode with sharp knee characteristics, enabling stable voltage reference under varying load and temperature conditions. Its 39 V nominal rating places it in the medium-voltage precision regulation range, where temperature coefficient is +0.07 %/°C (per Fig. 19), and total capacitance is ~1.5 pF at 2 V reverse bias.

The device uses alloy 42 leadframe with matte tin annealed finish, qualified to J-STD-020 Level 1 moisture sensitivity, and designed for reflow-compatible automated assembly. Thermal resistance junction-to-ambient is 417 °C/W on standard FR-4 layout, requiring derating above +25 °C per Figure 1.

Key Specifications

Pinout & Package

Package: SOT23 - three-terminal surface-mount plastic package with 0.915 mm body width, 2.40 mm length, and 1.30 mm height; UL 94V-0 rated molding compound; matte tin-plated alloy 42 leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C39 and MMSZ4702T1G, DDZX39F-13 offers the narrowest V_Z tolerance (±2.5%), lowest leakage (≤0.05 µA), and smallest SOT23 footprint-making it optimal for space-constrained, high-accuracy automotive and industrial references where thermal and electrical stability are prioritized over raw power headroom.

Availability

DDZX39F-13 is available at Aetrix Electronics and suitable for automotive engine control units, industrial sensor interfaces, telecom power supervision, and medical diagnostic equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DDZX39F-13 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 North America.

The DDZX series targets precision voltage reference and regulation in automotive, industrial, and communications systems-designed specifically for AEC-Q101 compliance, tight V_Z tolerance, and robust thermal performance in compact SOT23 packaging.

FAQ

What is the maximum reverse voltage (V_R) that DDZX39F-13 can withstand before breakdown?

The device exhibits sharp breakdown at its nominal zener voltage of 38.02–39.98 V when reverse-biased at 5 mA. Below 30 V reverse bias, leakage remains ≤0.05 µA; operation above 40 V is not specified and risks irreversible damage. The 39 V rating is the designed regulation point-not an absolute blocking voltage.

Does DDZX39F-13 require a minimum current to maintain regulation accuracy?

Yes. Regulation accuracy is specified at I_ZT = 5 mA. Below 1 mA, voltage deviation increases significantly due to knee region nonlinearity; the datasheet confirms usable regulation down to 0.5 mA, but V_Z shifts up to +3% from nominal. For stable 39 V reference, maintain ≥3 mA operating current.

Can DDZX39F-13 be used in parallel for higher power dissipation?

No. Parallel connection is not recommended due to mismatched zener voltages and thermal runaway risk-even with matched units, minor V_Z differences cause current hogging. For >300 mW requirements, use a single higher-power Zener or active regulation with a pass transistor driven by DDZX39F-13 as reference.

Is the SOT23 pinout of DDZX39F-13 compatible with standard Zener footprints?

Yes. Pin 1 is Anode, Pin 2 is Cathode, Pin 3 is NC-matching JEDEC-standard SOT23 orientation. The cathode band marking aligns with Pin 2, and the pad layout (X=0.8 mm, Y=0.9 mm, C=2.0 mm) matches Diodes Inc.'s published SOT23 land pattern for reliable solder joint formation and thermal transfer.