Microchip Technology 1N5277BUR-1/TR

Overview

1N5277BUR-1/TR from Microsemi is a surface-mount 160 V, ±5% tolerance Zener diode in DO-213AA (SOD80) MELF glass package, rated for 500 mW steady-state power dissipation, with 0.80 mA test current, 1700 Ω dynamic impedance at I_ZT, and 0.1 µA max reverse leakage at 116 V. It serves as a precision voltage reference or shunt regulator in low-current analog monitoring circuits.

For engineers reviewing the 1N5277BUR-1/TR datasheet, 1N5277BUR-1/TR pinout, 1N5277BUR-1/TR application, or 1N5277BUR-1/TR equivalent, key selection criteria include its 160 V nominal Zener voltage, DO-213AA hermetic glass packaging, 116 V maximum Zener voltage at 0.80 mA, +0.110 %/°C temperature coefficient, and suitability for space-constrained, high-reliability voltage regulation where minimal capacitance (<1.5 pF typical) and radiation hardness are required.

Technical Context

The 1N5277BUR-1/TR operates as a silicon planar Zener diode with metallurgical bonding between semiconductor die and end caps, enabling stable breakdown behavior across -65 °C to +175 °C junction temperature range. Its regulation occurs in reverse-biased avalanche mode above 6.8 V, with specified Zener voltage measured at thermal equilibrium under 0.80 mA dc test current.

It exhibits a positive temperature coefficient of +0.110 %/°C - consistent with higher-voltage Zeners in the 1N52xxBUR-1 family - and maintains ≤0.1 µA reverse leakage up to 116 V, supporting stable reference performance in low-power bias networks and overvoltage clamping where leakage-induced error must be minimized.

Key Specifications

Pinout & Package

DO-213AA (SOD80 or MLL34) hermetically sealed glass MELF package with two solderable end-cap terminals; cathode identified by single band on glass body. No internal leads - terminals are metallurgically bonded directly to die ends.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5277B-1/TR and BZX85C160-TR, the 1N5277BUR-1/TR delivers superior thermal resistance (250 °C/W), hermetic sealing, and radiation tolerance - making it the preferred choice for SMT-based, high-reliability reference designs where leakage, long-term stability, and environmental resilience are critical.

Availability

1N5277BUR-1/TR is available at Aetrix Electronics and suitable for high-voltage reference supplies, sensor overvoltage protection, low-power bias networks, and radiation-hardened timing references requiring stable component supply and traceable sourcing.

Supply support for 1N5277BUR-1/TR 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 Corporation (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability, radiation-tolerant, and high-voltage analog components for aerospace, defense, and industrial markets.

The 1N52xxBUR-1 series was designed to deliver JEDEC-standard Zener regulation in hermetic surface-mount form - targeting applications needing SMT compatibility, long-term parametric stability, and extended temperature operation without trade-offs in reliability.

FAQ

What is the Zener voltage tolerance of the 1N5277BUR-1/TR?

The 1N5277BUR-1/TR has a nominal Zener voltage of 160 V with a guaranteed tolerance of ±5%, meaning its actual breakdown voltage falls between 152 V and 168 V when measured at 0.80 mA dc test current and 25 °C. This tolerance is confirmed in the Electrical Characteristics table on page 3 of Microsemi's T4-LDS-0232-1 datasheet.

Does the 1N5277BUR-1/TR have a cathode band marking?

Yes, the 1N5277BUR-1/TR uses a single cathode band on the glass body to identify the cathode terminal, as specified in the Mechanical and Packaging section of the datasheet. The banded end must be held at a higher potential than the unbanded (anode) end for proper Zener regulation, and this marking is consistent across all DO-213AA-packaged 1N52xxBUR-1 devices.

What is the maximum power dissipation rating for the 1N5277BUR-1/TR?

The 1N5277BUR-1/TR is rated for a steady-state power dissipation of 0.5 W under defined mounting conditions: FR4 PCB with 1 oz copper and recommended footprint, with end cap temperature below 125 °C or ambient temperature below 50 °C. Derating is required above these temperatures per the curve in Figure 2 of the datasheet.

Is the 1N5277BUR-1/TR RoHS compliant?

Yes, the 1N5277BUR-1/TR is RoHS compliant (e3 suffix), as stated in the Part Nomenclature section of the datasheet. RoHS compliance applies to commercial-grade versions only and is verified per JEDEC J-STD-609, with annealed matte-tin plating on the end caps meeting lead-free solderability requirements per MIL-STD-750, method 2026.

What is the temperature coefficient of the 1N5277BUR-1/TR?

The 1N5277BUR-1/TR has a temperature coefficient of +0.110 %/°C, as listed in the Electrical Characteristics table. This value is measured between 25 °C and 125 °C at the rated test current and reflects the positive drift typical of Zeners above 6.8 V; it corresponds to approximately +176 mV/°C change in Zener voltage across the 160 V nominal value.