onsemi BZX84C30

Overview

BZX84C30 from ON Semiconductor is a 30 V ±5% tolerance surface-mount Zener diode in SOT-23 package, rated for 250 mW power dissipation at 25°C ambient, with nominal zener voltage of 28.0–32.0 V at 5 mA test current and dynamic impedance of 50 Ω at 20 mA, used for precision voltage regulation and overvoltage protection in low-power analog circuits.

For engineers reviewing the BZX84C30 datasheet, pinout, applications, or equivalent options, key selection criteria include zener voltage tolerance (±5%), thermal resistance (R_JA = 465°C/W), reverse leakage (≤0.05 µA at 21 V), temperature coefficient (+24.4 to +29.4 mV/°C), and SOT-23 footprint compatibility with space-constrained PCB layouts.

Technical Context

The BZX84C30 operates as a silicon planar epitaxial Zener diode optimized for stable voltage reference and clamping functions in DC bias networks and feedback paths. Its design incorporates controlled avalanche breakdown above 7 V, enabling predictable reverse conduction with low dynamic impedance and well-characterized temperature drift.

It is specified for operation across –55°C to +150°C junction temperature range, with thermal performance defined relative to FR-4 PCB mounting (76.2 mm × 114.3 mm). The device exhibits forward voltage ≤0.9 V at 10 mA and capacitance of 70 pF at 0 V reverse bias and 1 MHz.

Key Specifications

Pinout & Package

Package: SOT-23 (TO-236AB), 3-terminal plastic surface-mount package with cathode-marked lead configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5260BLT1G and 1N4745A, the BZX84C30 offers optimal balance of SOT-23 footprint, 250 mW rating, and 50 Ω impedance for automated high-volume production of compact power management circuits, while maintaining identical voltage tolerance and temperature coefficient behavior.

Availability

BZX84C30 is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC analog input stages, and medical infusion pump reference circuits requiring stable component supply and long-term lifecycle continuity.

Supply support for BZX84C30 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 manufacturer specializing in power management, analog, sensor, and connectivity solutions for automotive, industrial, and cloud power applications.

The BZX84 series belongs to ON Semiconductor's general-purpose Zener diode product line, engineered for reliable voltage regulation and transient suppression in cost-sensitive, high-volume electronic systems where SOT-23 packaging and tight tolerance are essential.

FAQ

What is the nominal zener voltage range of the BZX84C30 at 5 mA test current?

The BZX84C30 has a nominal zener voltage range of 28.0 V to 32.0 V when tested at I_Z = 5 mA, per the ON Semiconductor datasheet Rev. 1.10. This 4 V span reflects its ±5% tolerance grade and is measured under standard 25°C ambient conditions. The BZX84C30 maintains this specification across its full operating temperature range, with voltage drift characterized by its +24.4 to +29.4 mV/°C temperature coefficient.

Can the BZX84C30 be used in series to achieve higher regulated voltages?

Yes, the BZX84C30 can be connected in series to achieve higher regulated voltages, provided current-limiting resistors are sized to maintain minimum zener current across all devices. Each BZX84C30 contributes ~30 V, so two in series yield ~60 V. However, mismatched temperature coefficients may cause uneven voltage division; the BZX84C30's +24.4 to +29.4 mV/°C coefficient must be accounted for in precision applications. The BZX84C30 datasheet confirms series operation is supported under recommended conditions.

What is the maximum reverse leakage current for the BZX84C30 at 21 V?

The maximum reverse leakage current for the BZX84C30 at V_R = 21 V is 0.05 µA, as specified in the Electrical Characteristics table of the ON Semiconductor datasheet. This ultra-low leakage supports high-impedance bias networks and precision reference dividers where current draw must be minimized. The BZX84C30 achieves this performance while maintaining its 28.0–32.0 V zener voltage window and 50 Ω dynamic impedance at 20 mA.

Is the BZX84C30 RoHS compliant and halogen-free?

Yes, the BZX84C30 is RoHS compliant and halogen-free, consistent with ON Semiconductor's environmental policy and product marking standards. The device meets EU Directive 2011/65/EU (RoHS 2) and IEC 61249-2-21 for bromine and chlorine content. Compliance documentation, including material declarations and test reports, is available through ON Semiconductor's official product page and Aetrix Electronics' quality portal for the BZX84C30.

What is the forward voltage drop of the BZX84C30 at 10 mA?

The forward voltage drop of the BZX84C30 is guaranteed to be no more than 0.9 V at I_F = 10 mA, as stated in the datasheet's "VF Forward Voltage" note. This specification applies across the full operating temperature range and ensures predictable behavior when the device is forward-biased-such as in polarity-protection circuits or dual-function clamp/reference configurations. The BZX84C30 shares this forward characteristic with the entire BZX84 series.