onsemi 1N5953BG

Overview

1N5953BG from onsemi is a 3 W, 150 V nominal Zener voltage regulator diode in DO-41 axial package, rated for 10 mA test current (IZT), 2.5 Ω maximum Zener impedance at IZT, and 0.25 μA maximum reverse leakage at 114 V (VR), used for precision voltage reference and overvoltage protection in DC power supplies.

For engineers reviewing the 1N5953BG datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, thermal derating behavior, surge capability, Pb-free packaging confirmation, and real-world design implications for stable voltage clamping in industrial and automotive power circuits.

Technical Context

This Zener diode operates via silicon-oxide passivated junction technology, enabling tight ±5% tolerance (B-grade) and Class 3 ESD robustness (>16 kV HBM). Its 3 W steady-state dissipation at TL = 75°C with 24 mW/°C derating above that temperature defines thermal boundary conditions for PCB layout and heatsinking.

The device exhibits a 150 V nominal Zener voltage with min/max range of 142.5 V to 157.5 V at IZT = 10 mA, and maintains low dynamic impedance (ZZT ≤ 2.5 Ω) critical for regulation stability under load transients. Reverse leakage remains ≤0.25 μA at VR = 114 V, supporting high-impedance bias networks.

Key Specifications

Pinout & Package

Package: DO-41 axial-leaded plastic case (Case 59), void-free transfer-molded thermosetting material, cathode indicated by band, lead diameter 0.71–0.86 mm, overall length 25.4 mm min.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5953BG, the 1N5953BRLG offers identical performance in reel format for automation, while MMBZ5267ET1G trades 92% lower power handling and higher impedance for board-area savings-neither is pin-compatible due to differing packages and thermal mass.

Availability

1N5953BG is available at Aetrix Electronics and suitable for industrial power supply clamping, automotive battery monitoring, telecom line card protection, and PLC input conditioning requiring stable component supply across extended temperature ranges and high-surge environments.

Supply support for 1N5953BG 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 delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The 1N5913B Series Zener regulators were designed for high-reliability voltage reference and overvoltage protection in harsh-environment power systems, emphasizing robust surge handling, tight tolerance, and Pb-free manufacturability.

FAQ

What is the Zener voltage tolerance of the 1N5953BG?

The 1N5953BG has a ±5% Zener voltage tolerance, confirmed by the "B" suffix in its part number per ON Semiconductor's tolerance designation standard. At 10 mA test current (IZT), its nominal Zener voltage is 150 V, with a guaranteed range of 142.5 V (min) to 157.5 V (max). This tolerance is fully specified and tested per the datasheet's Electrical Characteristics table, making the 1N5953BG suitable for applications requiring predictable clamping thresholds without post-manufacturing calibration.

Can the 1N5953BG be used in surface-mount designs?

No, the 1N5953BG is strictly an axial-leaded DO-41 package device and cannot be directly mounted on surface-mount PCBs. Its mechanical outline (Case 59) requires through-hole mounting with 3/8″ lead length for rated 3 W dissipation. For SMT alternatives, consider the MMBZ5267ET1G (SOT-23, 150 V, 225 mW), but note its significantly lower power rating and higher impedance-designers must verify thermal and surge requirements before substitution. The 1N5953BG itself must be hand-soldered or wave-soldered in through-hole layouts.

What is the maximum reverse leakage current for the 1N5953BG?

The maximum reverse leakage current (IR) for the 1N5953BG is 0.25 μA, measured at VR = 114 V (80% of nominal VZ) and TL = 30°C. This value is guaranteed per the datasheet's Electrical Characteristics table and reflects the device's suitability for high-impedance bias networks and precision reference applications where leakage-induced error must be minimized. It remains valid across the full operating temperature range, though actual leakage increases slightly at elevated junction temperatures.

How does the 1N5953BG handle surge conditions?

The 1N5953BG is rated for 98 W nonrepetitive surge power at 1 ms pulse width, as defined in Figure 3 of the ON Semiconductor datasheet. This capability derives from its silicon-oxide passivated junction and thermal design, allowing it to absorb transient energy without degradation when used within specified limits. Surge testing assumes TJ = 25°C prior to pulse and adheres to rectangular waveform conditions-exceeding this rating risks permanent parametric shift or catastrophic failure. The 1N5953BG should not be relied upon for repetitive surges without verifying thermal recovery time.

Is the 1N5953BG RoHS-compliant and lead-free?

Yes, the "G" suffix in 1N5953BG explicitly denotes a Pb-free (RoHS-compliant) package, confirmed in the Ordering Information section of the ON Semiconductor datasheet. The device uses void-free, transfer-molded thermosetting plastic and meets JEDEC J-STD-020 reflow standards. Lead finish is corrosion-resistant and readily solderable, with maximum soldering temperature of 260°C at 1/16″ from case for 10 seconds. Full compliance documentation is available in ON Semiconductor's Pb-Free Strategy reference materials.