Diodes Incorporated UDZ9V1B-7

Overview

UDZ9V1B-7 from Diodes Incorporated is a surface-mount precision Zener diode with nominal zener voltage 9.1 V, ±2.5% tolerance, 200 mW power dissipation, 30 Ω dynamic impedance at 5 mA, and operating temperature range of –65 °C to +150 °C. It delivers stable voltage regulation in low-power reference and protection circuits, including power supply feedback loops and overvoltage clamp stages.

For engineers reviewing the UDZ9V1B-7 datasheet, UDZ9V1B-7 pinout, UDZ9V1B-7 application, or UDZ9V1B-7 equivalent, key selection criteria include zener voltage accuracy, thermal resistance (625 °C/W), cathode-band polarity marking, SOD323 package compatibility, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This device operates as a two-terminal voltage reference using controlled reverse-breakdown conduction. Its sharp breakdown characteristic and tight 2.5% voltage tolerance (8.85–9.23 V) enable precise regulation in analog sensing and feedback paths where minimal drift is critical.

Thermal performance is defined by R_θJA = 625 °C/W on FR-4 board with recommended pad layout, and it maintains stable operation across –65 °C to +150 °C. The cathode-band terminal identification and matte tin–annealed alloy-42 leadframe ensure reliable solderability and automated assembly compatibility.

Key Specifications

Pinout & Package

UDZ9V1B-7 uses the SOD323 package: ultra-small plastic case (1.30 mm × 1.70 mm × 0.90 mm), UL 94V-0 rated, with cathode identified by a band on the top surface. Terminals are matte tin–annealed alloy-42 leads, solderable per MIL-STD-202 Method 208.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX384-B9V1,115 and MMSZ5240B-TP, UDZ9V1B-7 offers superior voltage tolerance (±2.5% vs. ±2% and ±5%) and automotive qualification, making it optimal for safety-critical, space-constrained designs requiring long-term stability.

Availability

UDZ9V1B-7 is available at Aetrix Electronics and suitable for automotive body control modules, industrial sensor interfaces, consumer power adapter feedback circuits, and medical diagnostic equipment requiring stable component supply and AEC-Q101 compliance.

Supply support for UDZ9V1B-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.

The UDZ series belongs to Diodes' precision Zener diode product line, engineered specifically for high-accuracy voltage reference and overvoltage protection in automotive, industrial, and consumer power systems.

FAQ

What is the maximum reverse voltage (V_R) before significant leakage occurs?

At V_R = 6.0 V, the maximum reverse current is 0.5 µA. Leakage remains below 1 µA up to 6.0 V, confirming effective blocking behavior well below the 9.1 V zener threshold. This ensures minimal loading in high-impedance bias networks and reference dividers.

Is UDZ9V1B-7 suitable for use in high-frequency noise suppression?

No - its typical total capacitance is ~2.5 pF at 0 V bias (per Fig. 6), which is too low for effective RF filtering. It is designed for DC/low-frequency regulation and clamping, not EMI suppression. For noise filtering, dedicated TVS diodes or capacitors should be used in parallel.

Does the SOD323 package support reflow soldering per J-STD-020?

Yes - the device has Moisture Sensitivity Level 1 per J-STD-020D, meaning it can be subjected to standard Pb-free reflow profiles (peak 260 °C) without baking. The matte tin–annealed terminals meet MIL-STD-202 Method 208 solderability requirements.

How does temperature affect the zener voltage stability?

Per Fig. 7 and Fig. 8, UDZ9V1B-7 exhibits a temperature coefficient of approximately +0.06 %/°C near 9.1 V. This results in ~±0.54% drift over –40 °C to +125 °C ambient, consistent with its role in moderate-precision reference applications rather than ultra-stable metrology.