Microchip Technology 1N965BE3

Overview

1N965BE3 from Microsemi is a silicon 500 mW axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 15 V nominal Zener voltage at 16 mA test current, with ±5% tolerance (B suffix), 700 Ω maximum Zener impedance at I_ZT, and −65°C to +175°C operating temperature range. It serves as a precision voltage reference or shunt regulator in low-power analog circuits, power supply feedback paths, and overvoltage protection stages.

For engineers reviewing the 1N965BE3 datasheet, 1N965BE3 pinout, 1N965BE3 application, or 1N965BE3 equivalent, key selection criteria include its 15 V regulation point, 700 Ω dynamic impedance, RoHS-compliant matte-tin plating, DO-35 mechanical compatibility, and thermal resistance of 250 °C/W junction-to-lead - critical for stable operation in industrial and aerospace environments where ambient temperature swing and long-term reliability are design constraints.

Technical Context

The 1N965BE3 operates as a reverse-biased shunt regulator, maintaining a stable 15 V across its terminals when reverse current exceeds the knee region (I_ZK = 0.25 mA). Its Zener breakdown exhibits a +0.082 %/°C temperature coefficient, indicating positive drift with rising temperature - a key factor in temperature-compensated reference designs.

It is constructed using hermetically sealed glass DO-35 packaging with cathode band marking, tin-lead or RoHS-compliant matte-tin terminations, and meets MIL-STD-750 Method 1020 for ESD insensitivity. Thermal derating begins above 50 °C lead temperature, with maximum steady-state power reduced to 480 mW at T_L = 50 °C and 400 mW at T_L = 75 °C.

Key Specifications

Pinout & Package

Package: DO-35 (DO-204AH), hermetically sealed glass axial-leaded case with cathode indicated by colored band. Terminals are solderable matte-tin (RoHS-compliant per e3 suffix) per MIL-STD-750 Method 2026.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N965BE3, 1N4744A offers higher power handling but requires layout changes, while BZX55C15 delivers lower dynamic impedance at lower bias current but lacks documented radiation hardness and aerospace qualification - making 1N965BE3 preferable for mission-critical, high-reliability applications demanding proven DO-35 robustness and extended temperature compliance.

Availability

1N965BE3 is available at Aetrix Electronics and suitable for industrial power monitoring, aerospace voltage supervision, and precision analog sensor biasing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 1N965BE3 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

Microsemi (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability, radiation-hardened, and high-voltage analog components for defense, aerospace, and industrial markets.

The 1N957B–1N992B series was engineered for ruggedized voltage regulation in extreme environments - emphasizing hermetic sealing, wide temperature operation, and JEDEC-standardized parametric consistency across military and commercial variants.

FAQ

What is the Zener voltage tolerance for 1N965BE3?

The 1N965BE3 has a nominal Zener voltage of 15 V with ±5% tolerance, indicated by the "B" suffix per JEDEC registration. This means the actual measured V_Z falls between 14.25 V and 15.75 V at 16 mA test current and 25 °C ambient. The "e3" suffix confirms RoHS compliance but does not affect voltage tolerance. Tolerance remains fixed per part number suffix - no binning or post-screening is implied.

Does 1N965BE3 require heatsinking in standard PCB layouts?

No, the 1N965BE3 does not require external heatsinking under typical conditions. Its thermal resistance is 250 °C/W junction-to-lead (at 10 mm lead length) and 310 °C/W junction-to-ambient on FR4 with 4 mm² copper pads. At 130 mA I_ZM, power dissipation reaches 400 mW, resulting in ~100 °C junction rise - within its −65°C to +175°C rating. Standard hand-soldered or reflow-mounted DO-35 footprints suffice for most applications.

How does the temperature coefficient of 1N965BE3 impact circuit accuracy?

The 1N965BE3 has a +0.082 %/°C temperature coefficient, meaning its Zener voltage increases by approximately 12.3 mV per °C rise above 25 °C. Over a −40°C to +85°C range, this yields ±1.05 V drift - critical in precision references. Designers mitigate this by pairing it with negative-tempco components or using it in compensated topologies; the coefficient is well-documented and repeatable per Microsemi MicroNote 202.

Is 1N965BE3 suitable for surge protection applications?

Yes, the 1N965BE3 supports transient suppression with a 200 mA surge current rating (I_ZSM) for 1/120 sec pulses. Its 15 V clamping level protects downstream logic at safe margins, and its ESD insensitivity (MIL-STD-750 Method 1020) ensures robustness against handling-induced discharges. However, it is not rated for repetitive surges or lightning-level transients - use with series current-limiting resistors and coordinate with TVS diodes for high-energy events.

What is the forward voltage specification for 1N965BE3?

The forward voltage of 1N965BE3 is specified as 1.3 V maximum at 200 mA forward current, applicable to the 1N985B–1N992B subgroup per the datasheet. This value reflects anode-to-cathode conduction under high-current forward bias and is relevant for dual-role applications such as reverse-polarity protection or hybrid rectifier/Zener circuits - though its primary function remains reverse-biased regulation.