onsemi BZX84C15

Overview

BZX84C15 from ON Semiconductor (formerly Fairchild) is a 15 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 20 Ω at 20 mA and reverse leakage current ≤0.05 µA at 10.5 V, widely used for voltage regulation and overvoltage protection in low-power analog circuits.

For engineers reviewing the BZX84C15 datasheet, pinout, applications, or equivalent options, key selection considerations include its 15 V nominal zener voltage, 5% tolerance, 250 mW power rating, SOT-23 footprint compatibility, and thermal resistance of 465°C/W junction-to-ambient - critical for compact PCB designs requiring stable reference or clamping under variable load conditions.

Technical Context

The BZX84C15 operates as a silicon planar epitaxial Zener diode optimized for stable voltage reference and transient suppression in low-current applications. It exhibits a negative temperature coefficient below 5 V and positive above - at 15 V, its temperature coefficient is +9.2 mV/°C, enabling predictable drift compensation in precision bias networks.

Its electrical behavior is defined at three test currents (1 mA, 5 mA, 20 mA), with specified zener voltage min/max bounds and dynamic impedance across all points. Reverse capacitance is 110 pF at 0 V, and forward voltage is ≤0.9 V at 10 mA, supporting bidirectional signal conditioning and ESD-tolerant interface protection.

Key Specifications

Pinout & Package

SOT-23 plastic surface-mount package with cathode-marked lead identification; standardized 3-pin footprint compatible with automated placement and reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5245B and 1SMA5925BT3G, the BZX84C15 offers optimal balance of SOT-23 compactness, 250 mW capability, and predictable +9.2 mV/°C tempco - making it preferred for space-constrained, low-power analog subsystems where thermal budget and footprint are primary constraints.

Availability

BZX84C15 is available at Aetrix Electronics and suitable for voltage reference, overvoltage protection, and signal level shifting applications requiring stable component supply and consistent parametric performance across production batches.

Supply support for BZX84C15 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 discrete devices for automotive, industrial, and consumer markets.

The BZX84 series belongs to ON Semiconductor's general-purpose Zener diode product line, designed specifically for cost-effective, reliable voltage regulation and clamping in low-power electronic systems.

FAQ

What is the nominal zener voltage and tolerance of the BZX84C15?

The BZX84C15 has a nominal zener voltage of 15 V with a tolerance of ±5%, meaning its actual breakdown voltage falls between 13.8 V and 15.7 V when tested at specified currents (1 mA, 5 mA, or 20 mA). This tolerance band is marked as 'C' in the device suffix and is verified per ON Semiconductor's BZX84C3V3–BZX84C33 datasheet Rev. 1.10. The BZX84C15 maintains this specification across its full operating temperature range of –55°C to +150°C.

What is the maximum power dissipation rating for the BZX84C15?

The BZX84C15 is rated for 250 mW power dissipation at an ambient temperature of 25°C when mounted on a standard FR-4 PCB (76.2 mm × 114.3 mm). Its junction-to-ambient thermal resistance is 465°C/W, so power must be derated linearly above 25°C - for example, to ~125 mW at 75°C ambient. This rating applies to continuous DC operation; pulsed conditions require consultation with ON Semiconductor per Absolute Maximum Ratings Note 2.

Does the BZX84C15 have a specified temperature coefficient, and what is its value?

Yes, the BZX84C15 has a specified temperature coefficient of +9.2 mV/°C at I_Z = 5.0 mA, indicating a positive voltage drift with rising temperature. This value is measured and documented in the "Electrical Characteristics (Continued)" table of the official datasheet. The coefficient enables predictable thermal compensation in precision reference designs - for instance, pairing with a negative tempco element like an NTC thermistor to achieve near-zero net drift over temperature.

What is the reverse leakage current specification for the BZX84C15?

The BZX84C15 specifies a maximum reverse leakage current (I_R) of 0.05 µA at a reverse voltage (V_R) of 10.5 V and T_A = 25°C. This ultra-low leakage ensures minimal error contribution in high-impedance circuits such as voltage dividers, sensor bias networks, and battery-monitoring systems. Leakage remains well below 1 µA even at elevated temperatures, supporting reliable operation in extended-range industrial environments.

Is the BZX84C15 available in tape-and-reel packaging for automated assembly?

Yes, the BZX84C15 is supplied in EIA-481-compliant tape-and-reel format compatible with standard SMT pick-and-place equipment. Standard reels contain 3,000 units per 13-inch reel, with carrier tape conforming to SOT-23 pocket dimensions and embossed cavity depth. Aetrix Electronics provides full traceability and moisture sensitivity level (MSL) 1 handling per J-STD-020, ensuring readiness for lead-free reflow without preconditioning for the BZX84C15.