Diodes Incorporated DDZ39DSF-7

Overview

DDZ39DSF-7 from Diodes Incorporated is a precision 36.63–38.52 V Zener diode in SOD323F package, rated for 500 mW power dissipation on FR-4 PCB, with ±5% zener voltage tolerance at 5 mA test current, 85 Ω maximum zener impedance at 1 kHz, and 0.2 µA maximum reverse leakage at 30 V. It serves as a stable voltage reference in low-power analog monitoring circuits.

For engineers reviewing the DDZ39DSF-7 datasheet, DDZ39DSF-7 pinout, DDZ39DSF-7 application, or DDZ39DSF-7 equivalent, key selection criteria include tight V_Z tolerance (±5%), low temperature coefficient (<±5.5 mV/°C per Fig. 3), automotive-grade qualification readiness, and SOD323F footprint compatibility with high-density PCB layouts.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain a stable reference voltage across its cathode–anode terminals. Its 5 mA zener test current ensures minimal self-heating during calibration, while the 85 Ω dynamic impedance defines regulation accuracy under varying load conditions.

The device exhibits a negative temperature coefficient below ~5 V and transitions toward zero near 30–40 V (per Fig. 3), resulting in <±0.01%/°C drift over –65°C to +150°C ambient range. Its thermal resistance of 250°C/W (R_θJA) governs derating above +25°C - power must be reduced linearly to 0 W at +150°C (Fig. 1).

Key Specifications

Pinout & Package

Package: SOD323F - surface-mount plastic case (2.50 mm × 1.70 mm × 1.25 mm), moisture sensitivity level 1, matte tin-plated copper alloy leadframe, cathode band marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C39LT1G and MMSZ5255B-TP, DDZ39DSF-7 delivers tighter V_Z consistency (36.63–38.52 V), identical 500 mW rating, and smallest footprint - making it optimal for space-constrained, high-accuracy reference designs requiring long-term stability.

Availability

DDZ39DSF-7 is available at Aetrix Electronics and suitable for industrial sensor signal conditioning, automotive battery monitoring, programmable logic controller (PLC) input protection, and medical infusion pump power supervision requiring stable component supply and long-lifecycle support.

Supply support for DDZ39DSF-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 North America.

This part belongs to the DDZ series of precision Zener diodes, engineered specifically for high-stability voltage reference and overvoltage protection in automotive, industrial, and medical applications where tight tolerance and temperature stability are critical.

FAQ

What is the recommended minimum and maximum bias current for stable Zener operation?

The DDZ39DSF-7 is characterized at I_ZT = 5 mA, with stable regulation achieved between 1 mA and 20 mA. Below 1 mA, dynamic impedance rises sharply (>200 Ω); above 20 mA, self-heating exceeds 10°C rise, degrading voltage accuracy beyond ±0.1%. For best stability, operate between 3–10 mA.

Does DDZ39DSF-7 meet AEC-Q101 requirements for automotive use?

DDZ39DSF-7 is manufactured in IATF 16949-certified facilities and supports PPAP documentation. While not pre-qualified, it is designed to meet AEC-Q101 stress test requirements - including HTGB, HTRB, and temperature cycling - upon customer-specific qualification request per Diodes' automotive change control process.

How does the SOD323F package affect thermal performance compared to SOD-123?

SOD323F has higher thermal resistance (250°C/W) than SOD-123 (180°C/W) due to smaller pad area and thinner leadframe. To match SOD-123 thermal performance, increase copper pour area under the cathode/anode pads to ≥25 mm² per terminal and add thermal vias - achieving ≤200°C/W in optimized layouts.

Can DDZ39DSF-7 be used in series to generate higher reference voltages?

Yes - two DDZ39DSF-7 devices in series yield ~75 V nominal reference. However, mismatched V_Z tolerances (±5% each) result in up to ±7% total error. For multi-Zener references, use matched-pair devices or add trimming resistors; avoid series use in precision metrology applications.