Diodes Incorporated BZX84C27-7

Overview

BZX84C27-7 from Diodes Incorporated is a 27 V, 350 mW surface-mount Zener diode in SOT23 package, designed for precision voltage regulation and overvoltage protection in low-power analog and digital circuits. It delivers a nominal Zener voltage of 27 V at 2.0 mA test current, with ±10% tolerance (25.1–28.9 V), 80 Ω dynamic impedance at 2 mA, and <0.1 µA reverse leakage at 21.4 V, commonly used in power supply feedback loops and reference voltage generation.

For engineers reviewing the BZX84C27-7 datasheet, BZX84C27-7 pinout, BZX84C27-7 application, or BZX84C27-7 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (357 °C/W), low leakage at rated VR, SOT23 footprint compatibility, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage across its terminals under varying load and temperature conditions. Its planar die construction ensures consistent breakdown characteristics and low noise performance, while the SOT23 package enables high-density PCB layouts and compatibility with automated reflow assembly.

The device exhibits a negative temperature coefficient of −3.5 mV/°C near 27 V, enabling predictable drift behavior in temperature-sensitive references. Its 350 mW power rating is valid only when terminals are held at ambient temperature-derating applies above +25°C per Fig. 1 in DS18001 Rev. 33-2.

Key Specifications

Pinout & Package

Package: SOT23 - small-outline transistor package with gull-wing leads, molded plastic body (UL 94V-0), matte tin-plated alloy 42 leadframe, and polarity indicated by cathode band on top surface.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5256BS-7-F and BZX84-C27,115, the BZX84C27-7 offers superior low-current impedance (80 Ω @ 2 mA), tighter leakage control (<0.1 µA), and AEC-Q101 qualification-making it optimal for automotive feedback and precision reference use cases requiring low-power operation.

Availability

BZX84C27-7 is available at Aetrix Electronics and suitable for automotive power management, industrial sensor interfaces, and consumer power supply feedback requiring stable component supply, long-term lifecycle support, and AEC-Q101-compliant sourcing.

Supply support for BZX84C27-7 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 BZX84 series belongs to Diodes' precision Zener diode product line, engineered for voltage regulation, reference, and clamping in space- and power-constrained applications across automotive, industrial, and consumer markets.

FAQ

What is the maximum continuous Zener current for BZX84C27-7 at +25°C?

The absolute maximum DC Zener current is derived from P_D = 350 mW and V_Z = 27 V, yielding ~13 mA. However, the datasheet specifies I_ZT = 2.0 mA for parameter characterization, and operation beyond 10 mA risks exceeding thermal limits unless heatsinking or derating is applied per Fig. 1.

Is BZX84C27-7 suitable for use in automotive applications?

Yes-BZX84C27-7 is explicitly qualified to AEC-Q101 standards, tested for high-reliability operation across −65°C to +150°C junction temperature, and manufactured with green molding compound compliant with halogen/antimony restrictions required for automotive electronics.

How does the −3.5 mV/°C temperature coefficient affect circuit performance?

This negative coefficient means output voltage decreases by 3.5 mV per degree Celsius rise. In a 27 V reference, this results in ~−0.013% per °C drift-critical for high-accuracy systems; compensation techniques (e.g., complementary TC components) may be needed for <±0.1% total error over −40°C to +125°C.

Can BZX84C27-7 replace BZX84C24 or BZX84C30 in existing designs?

No-direct substitution is not recommended due to 3 V voltage step differences. A 24 V or 30 V Zener will shift regulation points by >11%, potentially violating downstream IC voltage tolerances. Layout and resistor values must be recalculated for each specific Zener voltage.