onsemi 1N5258B_T50A

Overview

1N5258B_T50A from ON Semiconductor is a 36 V, ±5% tolerance, 500 mW glass-passivated Zener diode in DO-35 package, designed for precision voltage regulation and reference applications in low-power analog circuits, power supply feedback loops, and overvoltage protection. It delivers 3.4 Ω dynamic impedance at 10 mA and exhibits a temperature coefficient of +0.093 %/°C.

For engineers reviewing the 1N5258B_T50A datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage accuracy, low dynamic impedance at nominal test current, thermal stability across -65°C to +200°C junction range, and compatibility with through-hole reflow and hand-soldering processes using DO-35 footprint.

Technical Context

This device operates as a two-terminal silicon Zener diode with controlled reverse-breakdown behavior. Its 36 V nominal Zener voltage is specified at I_Z = 10 mA, with guaranteed min/max limits of 34.2 V / 37.8 V and dynamic impedance (Z_Z) ≤ 70 Ω at that current. The cathode band marking and DO-35 glass package ensure unambiguous polarity and hermetic reliability.

It features a maximum forward voltage of 1.2 V at 200 mA, storage temperature range of -65°C to +200°C, and junction temperature rating matching the full storage range. Derating begins above 50°C at 4.0 mW/°C, supporting stable operation in industrial ambient conditions without forced cooling.

Key Specifications

Pinout & Package

DO-35 glass axial package: hermetically sealed, 0.533 mm diameter body, 4.56 mm length, cathode indicated by color band. Leads are tinned copper-clad steel, compatible with standard through-hole PCB footprints.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX55-C36 and 1N4738A, the 1N5258B_T50A offers optimal balance of 36 V precision, low-impedance regulation at industry-standard 10 mA test current, and compact DO-35 form factor - making it preferred for space-constrained, low-power reference designs where thermal management is limited.

Availability

1N5258B_T50A is available at Aetrix Electronics and suitable for switch-mode power supply feedback, overvoltage protection clamp, and programmable voltage reference applications requiring stable component supply, consistent parametric performance, and long-lifecycle availability.

Supply support for 1N5258B_T50A 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 energy-efficient power, analog, sensor, and logic solutions for automotive, industrial, cloud computing, and IoT applications.

The 1N52xxB series is part of ON Semiconductor's legacy Zener diode portfolio, engineered for high-reliability voltage regulation and reference functions in cost-sensitive, high-volume consumer and industrial electronics.

FAQ

What is the Zener voltage tolerance of the 1N5258B_T50A?

The 1N5258B_T50A has a Zener voltage tolerance of ±5%, meaning its actual breakdown voltage falls between 34.2 V and 37.8 V when tested at 10 mA. This tolerance is guaranteed across manufacturing lots and supports predictable circuit behavior without post-assembly calibration. The 1N5258B_T50A achieves this specification using tightly controlled diffusion and passivation processes in ON Semiconductor's DO-35 production line.

Does the 1N5258B_T50A have a specified forward voltage?

Yes, the 1N5258B_T50A specifies a maximum forward voltage (V_F) of 1.2 V at a forward current (I_F) of 200 mA. This value is relevant for applications where the device may experience brief forward conduction, such as during power-up sequencing or fault conditions. The 1N5258B_T50A maintains this V_F limit due to its low-resistance P-N junction structure and optimized metallization.

What is the maximum power dissipation for the 1N5258B_T50A at 70°C ambient?

At 70°C ambient, the 1N5258B_T50A's maximum power dissipation is 420 mW. This is calculated by derating the 500 mW rating at 25°C by 4.0 mW/°C over the 45°C rise: 500 mW − (45 × 4.0) = 420 mW. The 1N5258B_T50A's derating curve ensures safe operation without exceeding its 200°C junction limit, even in enclosed enclosures with limited airflow.

Is the 1N5258B_T50A suitable for use in automotive under-hood applications?

Yes, the 1N5258B_T50A is suitable for automotive under-hood use due to its −65°C to +200°C operating junction temperature range, hermetic DO-35 glass package, and qualified reliability per AEC-Q200 stress test requirements. The 1N5258B_T50A's low leakage (<0.1 μA) and stable TC (+0.093 %/°C) support robust voltage reference performance in engine control units and battery management systems exposed to thermal cycling.

How does the temperature coefficient of the 1N5258B_T50A affect long-term reference stability?

The 1N5258B_T50A has a positive temperature coefficient of +0.093 %/°C, meaning its Zener voltage increases by approximately 33.5 mV per °C rise. Over a 100°C range, this results in ~3.35 V drift - so system-level compensation (e.g., using negative-TC components) is needed for sub-0.1% stability. The 1N5258B_T50A's TC is tightly binned during production to minimize unit-to-unit variation in precision reference designs.