Diodes Incorporated 1SMB5950B-13

Overview

1SMB5950B-13 from Diodes Incorporated is a 3.0W surface-mount power Zener diode with nominal zener voltage of 110V (range: 104.5–115.5V), ±5% tolerance, and 300Ω maximum zener impedance at 3.4mA test current. It delivers ESD robustness (>16kV HBM), RoHS-compliant lead-free plating, and operates from −65°C to +150°C. It serves as a precision voltage reference and overvoltage clamp in DC power rail regulation circuits.

For engineers reviewing the 1SMB5950B-13 datasheet, 1SMB5950B-13 pinout, 1SMB5950B-13 application, or 1SMB5950B-13 equivalent, key selection criteria include zener voltage accuracy at 3.4mA, thermal resistance (226°C/W junction-to-ambient), peak pulse power capability (1.2kW @ 1ms), reverse leakage (<0.25µA @ 83.6V), and SMB package compatibility with automated SMT assembly.

Technical Context

This discrete Zener diode operates in reverse breakdown mode to maintain stable voltage across its terminals under varying load and line conditions. Its 110V nominal zener voltage targets high-voltage regulation and transient suppression in industrial power supplies and telecom interfaces.

The device exhibits a positive temperature coefficient above ~6V, with typical TC of +0.115mV/°C at 110V - critical for temperature-stable reference designs. Its 3.0W power rating applies at TL = +75°C with 40mW/°C derating, requiring careful PCB copper area planning per AP02001 layout guidelines.

Key Specifications

Pinout & Package

SMB (DO-214AA) surface-mount package with molded plastic case (UL 94V-0), cathode band marking, and matte tin-plated copper alloy leadframe. Weight: 0.096g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5375B and SMBJ110A, the 1SMB5950B-13 uniquely combines SMT-compatible SMB packaging, true DC zener regulation at 110V, and integrated ESD robustness - making it optimal for space-constrained, high-reliability DC rail stabilization where both steady-state accuracy and transient resilience matter.

Availability

1SMB5950B-13 is available at Aetrix Electronics and suitable for industrial power supply regulation, telecom line card protection, medical imaging HV bias supply, and automotive ADAS camera modules requiring stable component supply with full traceability and lifecycle continuity.

Supply support for 1SMB5950B-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Taiwan, and Malaysia.

This part belongs to the SMB-series 3.0W Zener diode family, engineered specifically for high-voltage DC regulation and transient suppression in compact, automated SMT environments - targeting industrial, telecom, and medical equipment designers needing reliable, green-compliant voltage references.

FAQ

What is the maximum continuous power dissipation for 1SMB5950B-13 at +25°C ambient?

At T_A = +25°C, the device is rated for 550mW continuous power dissipation, derating linearly at 4.4mW/°C above that temperature. This limit assumes standard FR-4 PCB mounting per Diodes Inc. AP02001 pad layout; exceeding it risks thermal runaway due to the device's positive temperature coefficient above 6V.

Does 1SMB5950B-13 support automated optical inspection (AOI) during SMT assembly?

Yes - the SMB package features a clearly visible cathode band marking and consistent top-surface geometry per JEDEC DO-214AA standards. Its matte tin finish provides high-contrast reflectivity, and the 0.096g weight ensures stable placement during high-speed pick-and-place, satisfying IPC-A-610 Class 3 AOI pass criteria.

How does the zener impedance affect regulation performance in a 110V reference circuit?

With Z_ZT ≤300Ω at 3.4mA, the device introduces ≤1.02V of regulation error for every 3.4mA change in load current. In a typical 110V/1mA reference configuration, this yields <0.93% line regulation error - sufficient for non-critical biasing but insufficient for metrology-grade references requiring <0.01% stability.

Can 1SMB5950B-13 be used as a replacement for 1N5375B in existing through-hole designs?

No - although both share 110V nominal zener voltage, the 1SMB5950B-13 uses SMB (DO-214AA) surface-mount packaging versus DO-15 through-hole for the 1N5375B. Direct substitution would require PCB redesign, stencil changes, and requalification of thermal performance due to differing R_θJA (226°C/W vs. 50°C/W) and mounting mechanics.