Diodes Incorporated DDZ3V3ASF-7

Overview

DDZ3V3ASF-7 from Diodes Incorporated is a precision 3.3 V Zener diode in SOD323F package, designed for voltage regulation and reference applications with ±3.2% zener voltage tolerance (3.16–3.38 V at 20 mA), 130 Ω dynamic impedance, and 20 µA reverse leakage at 1 V. It delivers stable 500 mW power dissipation on FR-4 PCBs and supports automotive-grade assembly via RoHS-compliant, halogen-free construction.

For engineers reviewing the DDZ3V3ASF-7 datasheet, DDZ3V3ASF-7 pinout, DDZ3V3ASF-7 application, or DDZ3V3ASF-7 equivalent, this device is selected for low-voltage reference stability, compact board space constraints, tight thermal resistance (250 °C/W), and compatibility with automated SMT processes in power management and signal conditioning circuits.

Technical Context

This Zener diode operates in reverse breakdown to maintain a precise DC reference voltage under varying load and temperature conditions. Its 3.3 V nominal zener voltage targets low-power logic supply monitoring, ADC reference stabilization, and overvoltage clamp protection in 3.3 V systems.

Designed for surface-mount use on standard FR-4 PCBs, it features a cathode band marking, matte tin–annealed copper alloy terminals, and moisture sensitivity level 1 per J-STD-020 - enabling robust reflow compatibility without preconditioning.

Key Specifications

Pinout & Package

Package: SOD323F - ultra-compact surface-mount plastic package (2.50 mm × 1.70 mm × 1.25 mm) with molded green compound (UL 94V-0), cathode band marking, and matte tin–annealed copper alloy leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX384-B3V3 and MMSZ4685T1G, DDZ3V3ASF-7 offers tighter voltage tolerance and lower leakage, making it preferable for precision 3.3 V reference and battery-sensitive applications - though its 130 Ω Z_ZT sits between the two alternatives' impedance values.

Availability

DDZ3V3ASF-7 is available at Aetrix Electronics and suitable for 3.3 V power monitoring, ADC reference stabilization, USB-C voltage clamping, and low-power IoT node supervision requiring stable component supply and full RoHS/Green compliance.

Supply support for DDZ3V3ASF-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, specializing in high-reliability, application-optimized components for industrial, automotive, and consumer markets.

This device belongs to the DDZxxASF/BSF precision Zener series, engineered specifically for high-accuracy voltage reference and regulation in compact, thermally constrained SMT designs - emphasizing tight tolerance, low leakage, and automotive-ready process control.

FAQ

What is the maximum continuous reverse current the DDZ3V3ASF-7 can sustain without degradation?

The DDZ3V3ASF-7 is rated for 20 mA test current (I_ZT) and 500 mW power dissipation. Sustained reverse current must be limited to ensure junction temperature stays within −65 to +150 °C. At 25 °C ambient on FR-4, max continuous I_Z ≈ 150 mA is theoretically possible but not recommended; typical design practice limits to ≤50 mA with appropriate thermal derating per Figure 1.

Does the SOD323F package support lead-free reflow profiles per JEDEC J-STD-020?

Yes - the SOD323F package has moisture sensitivity level 1 per J-STD-020, meaning it may be stored indefinitely at ≤30 °C/60% RH without baking. It is qualified for standard Pb-free reflow profiles with peak temperatures up to 260 °C, compatible with IPC/JEDEC J-STD-020D.2 specifications.

How does the 3.3 V zener voltage drift with temperature?

Per Figure 3 in DS31987 Rev. 23, the temperature coefficient for 3.3 V Zeners in this family is approximately +2.5 mV/°C near 25 °C. This means V_Z increases ~0.25 V over a 100 °C rise - a predictable, linear shift used in temperature-compensated reference designs when paired with negative-TC components.

Can DDZ3V3ASF-7 replace a 3.3 V TL431-based shunt regulator in low-current applications?

Yes - for currents ≤10 mA and where ±3.2% initial tolerance is acceptable, DDZ3V3ASF-7 provides simpler, lower-cost regulation than TL431. However, it lacks adjustable output and active error amplification; use only where fixed 3.3 V reference suffices and load regulation demands are met by its 130 Ω Z_ZT.