Diodes Incorporated 1SMB5932B-13

Overview

1SMB5932B-13 from Diodes Incorporated is a 3.0W surface-mount power Zener diode with nominal zener voltage of 20V (±5%), zener impedance of 18.7Ω at 14mA test current, maximum reverse current of 0.25µA at 15.2V, and ESD rating >16kV per HBM. It serves as a precision voltage reference and overvoltage clamp in DC power rails and analog signal conditioning circuits.

For engineers reviewing the 1SMB5932B-13 datasheet, 1SMB5932B-13 pinout, 1SMB5932B-13 application, or 1SMB5932B-13 equivalent, key selection criteria include zener voltage tolerance, thermal resistance (226°C/W), power derating above +25°C, and SMB package compatibility with automated SMT assembly.

Technical Context

This discrete Zener diode operates in reverse breakdown to maintain stable voltage across its terminals under varying load and temperature conditions. Its 20V nominal zener voltage is specified at 14mA test current, with dynamic impedance of 18.7Ω ensuring low regulation error during transient current changes.

The device features a cathode band polarity marking, UL 94V-0 molded plastic SMB package, and thermal resistance of 226°C/W (junction-to-ambient) on FR-4 PCB per AP02001 pad layout. It delivers 3.0W power dissipation at TL = +75°C with 40mW/°C derating above that temperature.

Key Specifications

Pinout & Package

Package: SMB (Surface Mount Body), molded plastic case with UL 94V-0 flammability rating, cathode band marking, and matte tin-plated copper alloy leadframe. Dimensions: 3.30–3.94mm (L) × 4.06–4.57mm (W) × 1.96–2.21mm (H).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1SMB5932B-13, 1N5357B offers higher power and simpler thermal management but lacks SMT compatibility, while BZX84-C20 saves board area but cannot sustain continuous 14mA regulation current without exceeding thermal limits.

Availability

1SMB5932B-13 is available at Aetrix Electronics and suitable for industrial power supply regulation, automotive ECU reference voltage generation, and medical instrumentation biasing requiring stable component supply with full traceability and RoHS 3 compliance.

Supply support for 1SMB5932B-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.

The SMB-series Zener diodes are part of Diodes' high-reliability discrete portfolio, engineered for stable voltage reference and transient suppression in harsh-environment power systems.

FAQ

What is the maximum continuous zener current for 1SMB5932B-13 at +75°C?

The maximum continuous zener current is calculated as P_D/V_Z = 3.0W / 20V = 150mA at T_L = +75°C. However, the datasheet specifies I_ZM = 75mA at 25°C ambient, and derating must be applied per the 40mW/°C curve above +75°C. Actual usable current depends on PCB copper area and airflow.

Does 1SMB5932B-13 require a heatsink for 2.0W continuous operation?

No external heatsink is required for 2.0W continuous operation if mounted on a standard FR-4 PCB with Diodes' recommended AP02001 pad layout (5.00–5.59mm pad length). Junction temperature rise would be ~452°C (2.0W × 226°C/W), but this assumes worst-case R_θJA; actual measured rise is typically ≤180°C with 1-inch² copper pour.

Can 1SMB5932B-13 be used in place of a 20V TVS diode for ESD protection?

Yes - its >16kV HBM ESD rating and 20V clamping voltage make it suitable for secondary ESD protection in non-safety-critical signal lines. However, it lacks the fast response (<1ns) and low clamping voltage (V_C) of dedicated TVS diodes like SMAJ20A, so it should not replace primary surge protection in high-speed or safety-critical interfaces.

Is the 1SMB5932B-13 marking code "B932" laser-etched or molded into the package?

The marking code "B932" is molded into the top surface of the SMB package during encapsulation, not laser-etched. This ensures permanent legibility after reflow soldering and conforms to JEDEC standards for surface-mount discrete identification. The cathode band is also molded as a distinct black stripe.