Diodes Incorporated BZT52C18-7

Overview

BZT52C18-7 from Diodes Incorporated is a surface-mount Zener diode with a nominal zener voltage of 18 V, ±5.6% tolerance (16.8–19.1 V), 500 mW power dissipation at TL = +75°C, and 370 mW at TA = +25°C. It features SOD123 package, 45 Ω maximum zener impedance at 5 mA test current, and operates across –65 °C to +150 °C. It serves as a precision voltage reference or overvoltage clamp in low-power DC regulation circuits.

For engineers reviewing the BZT52C18-7 datasheet, BZT52C18-7 pinout, BZT52C18-7 application, or BZT52C18-7 equivalent, key selection criteria include zener voltage tolerance, thermal resistance (RθJA = 338 °C/W), reverse leakage at rated VR (0.1 µA @ 12.4 V), temperature coefficient (+12.6 mV/°C), and AEC-Q101 qualification status for automotive-grade reliability.

Technical Context

This Zener diode uses planar die construction for stable breakdown characteristics and low dynamic impedance. Its cathode-band polarity and matte tin-plated alloy 42 leadframe ensure reliable solderability and automated assembly compatibility.

Designed for medium-current general-purpose regulation, it delivers 18 V stabilization at 5 mA test current with 0.1 µA reverse leakage at 12.4 V and exhibits a positive temperature coefficient of +12.6 mV/°C - enabling predictable drift compensation in temperature-sensitive references.

Key Specifications

Pinout & Package

Package: SOD123 - surface-mount plastic case with cathode band marking, 0.010 g weight, UL 94V-0 flammability rating, and moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5245B-7-F and BZX84-C18, BZT52C18-7 offers superior thermal capability (370 mW), lower dynamic impedance (45 Ω), and AEC-Q101 certification - making it the only choice for automotive and industrial designs demanding long-term stability under thermal stress.

Availability

BZT52C18-7 is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, and embedded power supply reference circuits requiring stable component supply and full traceability.

Supply support for BZT52C18-7 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 BZT52 series belongs to Diodes' general-purpose Zener diode product line, engineered for cost-effective, high-yield voltage regulation and protection in commercial and automotive applications - emphasizing AEC-Q101 compliance, tight tolerances, and SMT manufacturability.

FAQ

What is the maximum reverse voltage (V_R) at which leakage remains ≤0.1 µA?

The BZT52C18-7 guarantees ≤0.1 µA reverse leakage at V_R = 12.4 V, as specified in the Electrical Characteristics table. This value is measured at T_A = +25°C and defines the upper limit of safe non-conducting operation before entering the zener breakdown region.

Can BZT52C18-7 be used in place of a 15 V Zener for higher-voltage rail stabilization?

No - BZT52C18-7 is specifically rated for 18 V nominal breakdown and must not substitute for lower-voltage Zeners without circuit revalidation. Its 16.8–19.1 V range would cause over-regulation in 15 V systems, potentially damaging downstream components or violating safety margins.

Is the SOD123 package compatible with reflow profiles for lead-free soldering?

Yes - the device uses matte tin plating over alloy 42 leadframe and is qualified per J-STD-020 moisture sensitivity level 1, supporting standard Pb-free reflow profiles (peak 260°C, 30 sec max). The UL 94V-0 mold compound withstands repeated thermal cycling without delamination.

Does the +12.6 mV/°C temperature coefficient indicate voltage increase or decrease with rising temperature?

The +12.6 mV/°C coefficient means the zener voltage increases by approximately 12.6 mV per degree Celsius rise in junction temperature. This positive drift is characteristic of Zeners above ~5.6 V and must be accounted for in precision reference designs operating across wide temperature ranges.