onsemi BZX85C3V6_T50R

Overview

BZX85C3V6_T50R from onsemi is a 3.6 V ±5% Zener diode in DO-41 glass package, rated for 1.0 W power dissipation at 25°C, with 60 Ω zener impedance at 5 mA test current and 1 μA maximum leakage at 1 V reverse voltage. It provides precise voltage regulation in low-power analog reference and overvoltage protection circuits.

For engineers reviewing the BZX85C3V6_T50R datasheet, pinout, applications, or equivalent options, key selection criteria include zener voltage tolerance (±5%), thermal derating slope (6.67 mW/°C above 50°C), junction temperature range (–65°C to +200°C), and DO-41 axial lead mechanical compatibility.

Technical Context

This device operates as a two-terminal voltage reference diode, conducting in reverse breakdown when reverse-biased above its nominal 3.6 V zener voltage. Its 60 Ω dynamic impedance at I_Z = 5 mA ensures stable regulation under moderate load variations.

The DO-41 glass package enables hermetic sealing and high-temperature operation up to +200°C junction temperature. Thermal derating begins at 50°C ambient, reducing power capability linearly by 6.67 mW per °C rise.

Key Specifications

Pinout & Package

DO-41 glass axial-leaded package with cathode indicated by a single color band. Leads are tinned copper-clad steel; body diameter 2.03–2.72 mm, length ≥25.4 mm, lead spacing 5.20 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4728A and BZX55C3V6, the BZX85C3V6_T50R uniquely balances 3.6 V precision, 1.0 W robustness, and DO-41 mechanical reliability-making it optimal for industrial power rails and legacy replacement where thermal margin and voltage accuracy are jointly critical.

Availability

BZX85C3V6_T50R is available at Aetrix Electronics and suitable for industrial control systems, automotive body electronics, and medical instrumentation requiring stable component supply with full traceability and long-lifecycle support.

Supply support for BZX85C3V6_T50R 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

onsemi (formerly ON Semiconductor) is a global semiconductor manufacturer specializing in energy-efficient power management, analog, and sensor solutions for automotive, industrial, and cloud infrastructure markets.

The BZX85 series was designed for general-purpose voltage regulation and protection in cost-sensitive, high-reliability applications-emphasizing wide temperature operation, hermetic packaging, and consistent parametric performance across manufacturing lots.

FAQ

What is the nominal zener voltage and tolerance of BZX85C3V6_T50R?

The BZX85C3V6_T50R has a nominal zener voltage of 3.6 V with a tolerance of ±5%, meaning its actual breakdown voltage falls between 3.4 V and 3.8 V when tested at 5 mA. This specification is guaranteed across the full operating temperature range and is validated per onsemi's BZX85C3V3–BZX85C56 datasheet Rev. 2 (October 2017). The BZX85C3V6_T50R achieves this tolerance using process-controlled diffusion and laser trimming during manufacture.

Can BZX85C3V6_T50R be used in surface-mount designs?

No, the BZX85C3V6_T50R is exclusively offered in the through-hole DO-41 axial glass package and is not available in SMD variants such as SOD-123 or DO-213AB. Its leads require hole mounting and wave or hand soldering. For surface-mount equivalents, consider the MMBZ5226BS (3.6 V, SOT-23) or BZX384-C3V6 (3.6 V, SOD-323), though these differ in power rating and thermal behavior. The BZX85C3V6_T50R remains optimal for legacy through-hole boards and high-reliability through-hole assemblies.

What is the maximum allowable power dissipation for BZX85C3V6_T50R at 75°C ambient?

At 75°C ambient, the BZX85C3V6_T50R must be derated from its 1.0 W rating at 25°C. With a derating factor of 6.67 mW/°C above 50°C, the allowable power is reduced by (75 – 50) × 6.67 mW = 166.75 mW, resulting in a maximum dissipation of 833 mW. This value ensures junction temperature stays within the –65°C to +200°C limit. The BZX85C3V6_T50R datasheet specifies this linear derating curve explicitly for thermal design validation.

How does the zener impedance of BZX85C3V6_T50R affect regulation accuracy?

The BZX85C3V6_T50R exhibits 60 Ω zener impedance at 5 mA, meaning a 1 mA change in zener current causes approximately 60 mV shift in regulated voltage. This directly impacts regulation accuracy under varying load conditions. For example, if load current changes by 2 mA, output voltage shifts ~120 mV - a key consideration in precision references. The BZX85C3V6_T50R's Z_Z is measured under standardized thermal equilibrium conditions per JEDEC, ensuring repeatable performance across units.

Is BZX85C3V6_T50R suitable for ESD protection in USB data lines?

No, the BZX85C3V6_T50R is not optimized for high-speed ESD protection on USB data lines due to its relatively slow response time (>1 ns) and high capacitance (~50 pF) inherent to the DO-41 glass package. It lacks the low clamping voltage and sub-nanosecond response required for USB 2.0 compliance. For that application, purpose-built TVS diodes like the ESD9X3.3S or USBLC6-2SC6 are recommended. The BZX85C3V6_T50R is best applied in low-frequency, high-energy clamping scenarios such as power rail protection.