onsemi 1N5386B

Overview

1N5386B from onsemi is a 5 W axial-lead Zener diode with nominal zener voltage of 180 V, ±5% tolerance, maximum zener impedance of 5 Ω at 430 mA test current, and surge rating of 1750 A at 8.3 ms. It operates as a precision voltage reference or overvoltage clamp in high-voltage DC power supplies and industrial control circuits.

For engineers reviewing the 1N5386B datasheet, pinout, applications, or equivalent options, key selection criteria include its 180 V nominal regulation, low 5 Ω dynamic impedance at rated current, 1.0 V leakage current limit at 137 V, and axial Surmetic 40 package compatibility with through-hole PCB assembly and manual soldering at 260°C.

Technical Context

This device uses silicon-oxide passivated junction technology to achieve tight voltage tolerance and stable regulation under varying thermal and load conditions. Its 5 W steady-state power dissipation is thermally managed via axial leads with 25 °C/W junction-to-lead thermal resistance at 3/8″ lead length.

The 1N5386B exhibits a positive temperature coefficient above 10 V (≈0.1 mV/°C per volt), enabling predictable drift in high-temperature environments. Its 8.3 ms non-repetitive surge capability supports transient suppression in rectified AC line applications without derating.

Key Specifications

Pinout & Package

Package: Axial-lead plastic case (Surmetic 40, Case 017AA), 8.38–8.89 mm body length, 3.30–3.68 mm diameter, cathode identified by painted band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5386B, the 1N5386BRLG offers identical regulation performance in automated manufacturing, while the SMCJ180A trades precision for faster transient response-making 1N5386B the sole choice where stable 180 V DC reference is required.

Availability

1N5386B is available at Aetrix Electronics and suitable for industrial power supply regulation, high-voltage sensor biasing, and AC line surge clamping requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for 1N5386B 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 (Semiconductor Components Industries, LLC) is a global semiconductor supplier specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The 1N53 Series belongs to onsemi's high-power Zener regulator product line, engineered for precision voltage reference and overvoltage protection in harsh-environment power systems where reliability and parameter stability are critical.

FAQ

What is the nominal zener voltage and tolerance of the 1N5386B?

The 1N5386B has a nominal zener voltage of 180 V with a guaranteed tolerance of ±5%, corresponding to a minimum of 171 V and maximum of 189 V at IZT = 430 mA. This tolerance is defined per JEDEC standards and applies specifically to the "B" suffix variant, ensuring consistent regulation in high-voltage feedback networks where tight setpoint accuracy is required.

How does the 1N5386B handle thermal management in continuous operation?

The 1N5386B relies on axial lead conduction for heat dissipation, with a junction-to-lead thermal resistance of 25 °C/W at 3/8″ lead length. At 5 W dissipation, this yields a 125°C temperature rise above lead temperature; therefore, maintaining TL ≤ 25°C (via heatsinking or airflow) ensures TJ remains within the safe 150°C DC limit. Derating begins above 25°C at 40 mW/°C.

Can the 1N5386B be used as a direct replacement for older 1N5386 (non-B) parts?

No-the 1N5386B is not a drop-in replacement for legacy 1N5386 devices. The "B" suffix denotes tighter ±5% tolerance and updated test conditions per JEDEC; non-B variants have looser tolerances and different IZM ratings. Substituting requires verification of system-level regulation margin and thermal design, as the 1N5386B's higher IZM (430 mA) and lower ZZT (5 Ω) alter loop dynamics in feedback circuits.

What is the maximum allowable reverse leakage current for the 1N5386B and at what voltage is it specified?

The 1N5386B specifies a maximum reverse leakage current (IR) of 4.0 mA at VR = 137 V. This value is measured under DC conditions at TA = 25°C and defines the upper bound of standby current draw when the diode is reverse-biased below its zener knee, critical for low-power bias networks in high-impedance sensor interfaces.

Does the 1N5386B support Pb-free soldering processes, and what is the maximum solder temperature?

Yes, the 1N5386B is offered in Pb-free packaging (indicated by the "G" suffix) and supports standard lead-free reflow profiles. The maximum lead temperature for soldering is 260°C at a distance of 1/16 inch from the case for 10 seconds, per onsemi's mechanical specifications. This allows compatibility with IPC-J-STD-020-compliant assembly without compromising junction integrity or plastic encapsulant stability.