onsemi BZX84C5V1

Overview

BZX84C5V1 from ON Semiconductor (formerly Fairchild) is a 5.1 V ±5% tolerance surface-mount Zener diode in SOT-23 package, rated for 250 mW power dissipation at 25°C ambient, with typical zener impedance of 15 Ω at 20 mA and reverse leakage current ≤2 µA at 2.0 V, used for voltage regulation and reference in low-power analog circuits.

For engineers reviewing the BZX84C5V1 datasheet, pinout, applications, or equivalent options, key selection factors include its precise 5.1 V nominal zener voltage, low dynamic impedance, tight 5% tolerance (C-grade), temperature coefficient of +1.2 mV/°C, and compatibility with automated SMT assembly on FR-4 PCBs.

Technical Context

The BZX84C5V1 operates as a silicon planar epitaxial Zener diode optimized for stable voltage reference in bias networks, overvoltage clamping, and signal-level regulation. It exhibits a nominal breakdown voltage of 5.1 V with ±5% tolerance, specified at test currents of 1.0 mA, 5.0 mA, and 20 mA.

Its thermal performance is defined by a junction-to-ambient thermal resistance of 465°C/W (on FR-4 board) and junction-to-lead resistance of 220°C/W, enabling reliable operation within -55°C to +150°C junction temperature range. Capacitance is 225 pF at 0 V and 1 MHz.

Key Specifications

Pinout & Package

Package: SOT-23 (TO-236AB), 3-terminal plastic surface-mount package with cathode-marked lead. Standard JEDEC MO-215 outline; body dimensions 2.9 mm × 1.3 mm × 1.0 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5221BS-7-F and 1SMA5915BT3G, the BZX84C5V1 offers optimal balance of SMT compatibility, 250 mW rating, and 15 Ω impedance for space-constrained, low-power reference and clamping-without requiring layout changes or derating for thermal performance.

Availability

BZX84C5V1 is available at Aetrix Electronics and suitable for voltage reference design, ESD protection circuits, and analog bias networks requiring stable component supply across consumer, industrial, and automotive electronics programs.

Supply support for BZX84C5V1 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

ON Semiconductor is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The BZX84 series belongs to ON Semiconductor's general-purpose Zener diode product line, engineered for cost-effective, high-volume voltage regulation and protection in space-constrained SMT designs.

FAQ

What is the nominal zener voltage and tolerance of the BZX84C5V1?

The BZX84C5V1 has a nominal zener voltage of 5.1 V with a ±5% tolerance (C-grade), verified at 20 mA test current. Its voltage range spans 5.0 V (minimum) to 5.9 V (maximum) under those conditions, making it suitable for 5 V system reference applications where moderate accuracy is acceptable without trimming.

What is the maximum power dissipation rating for the BZX84C5V1?

The BZX84C5V1 is rated for 250 mW power dissipation at TA = 25°C when mounted on a standard FR-4 PCB (76.2 mm × 114.3 mm). Derating is required above 25°C ambient, following the 465°C/W junction-to-ambient thermal resistance specification; at 70°C ambient, usable power drops to approximately 140 mW.

Does the BZX84C5V1 have a specified zener impedance, and what does it mean for circuit design?

Yes-the BZX84C5V1 has a maximum zener impedance (ZZ) of 15 Ω at IZ = 20 mA. This low dynamic impedance ensures minimal output voltage variation (<0.3 V) under ±1 mA load current changes, supporting stable regulation in precision analog bias and reference circuits where source impedance matters.

What is the reverse leakage current specification for the BZX84C5V1, and at what voltage is it measured?

The BZX84C5V1 specifies a maximum reverse leakage current (IR) of 2 µA at VR = 2.0 V. This low leakage supports high-impedance node stabilization-such as in comparator reference inputs or microcontroller reset circuits-where unintended current draw must remain below nanoampere-level thresholds.

How does the temperature coefficient of the BZX84C5V1 affect its performance across operating temperature?

The BZX84C5V1 has a temperature coefficient of +1.2 mV/°C at IZ = 5 mA, meaning its zener voltage increases linearly with temperature. Over a -40°C to +85°C ambient range, this results in ~150 mV total drift-critical for applications requiring long-term stability, where compensation or selection of tighter-tempco variants may be needed.