Vishay General Semiconductor - Diodes Division P6SMB9.1A-E3/5B

Overview

P6SMB9.1A-E3/5B from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMB (DO-214AA) package, designed to protect sensitive electronics against voltage transients induced by inductive load switching and lightning surges. It features a 7.78 V stand-off voltage (V_WM), 8.65–9.55 V breakdown voltage (V_BR) at 1.0 mA test current, 13.4 V maximum clamping voltage (V_C) at 44.8 A peak pulse current, and 600 W peak pulse power rating with 10/1000 μs waveform.

For engineers reviewing the P6SMB9.1A-E3/5B datasheet, P6SMB9.1A-E3/5B pinout, P6SMB9.1A-E3/5B application, or P6SMB9.1A-E3/5B equivalent, this device serves as a RoHS-compliant, commercial-grade transient suppressor for DC power rail and signal line protection in consumer, industrial, and telecom systems where fast response (<1 ns), low clamping ratio (V_C/V_BR ≈ 1.47), and AEC-Q101-qualified variants are critical selection criteria.

Technical Context

The P6SMB9.1A-E3/5B operates as a unidirectional avalanche diode, conducting only when reverse voltage exceeds its breakdown threshold. Its glass-passivated junction ensures stable V_BR tolerance (±5%) and low incremental surge resistance, enabling precise clamping under repetitive 10/1000 μs transients at 0.01% duty cycle.

Thermal performance is defined by R_θJA = 100 °C/W (junction-to-ambient, on minimum pad layout) and T_J(max) = 150 °C, supporting operation in compact PCB layouts without forced cooling. The cathode band marking identifies polarity, and matte tin-plated leads comply with J-STD-002 solderability standards.

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), surface-mount, unidirectional configuration with cathode band marking. Dimensions: 5.59 mm × 4.06 mm × 2.20 mm (L × W × H); matte tin-plated leads, J-STD-002 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with SMAJ9.0A and 1.5SMC9.0A, the P6SMB9.1A-E3/5B offers optimal balance of clamping performance, SMB footprint compatibility, and commercial-grade cost for mid-tier surge protection-making it preferred for space-constrained consumer and industrial designs where 600 W rating suffices.

Availability

P6SMB9.1A-E3/5B is available at Aetrix Electronics and suitable for automotive power rail protection, industrial sensor signal line protection, consumer USB port protection, and telecom DC feeder protection requiring stable component supply, RoHS compliance, and MSL Level 1 reflow readiness.

Supply support for P6SMB9.1A-E3/5B 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

Vishay General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, and protection devices with emphasis on reliability, precision, and automotive qualification.

The P6SMB Series targets cost-sensitive, high-volume transient suppression needs in consumer, industrial, and automotive electronics-designed for robustness under repetitive surge stress and compatibility with automated SMT assembly.

FAQ

What is the maximum clamping voltage of the P6SMB9.1A-E3/5B under rated surge conditions?

The P6SMB9.1A-E3/5B has a maximum clamping voltage (V_C) of 13.4 V at 44.8 A peak pulse current with a 10/1000 μs waveform. This value is guaranteed across temperature and production lots per Vishay's datasheet revision 09-Jan-2024, Document Number 88370. It reflects the actual voltage seen by protected circuitry during worst-case transient events, making it critical for validating downstream IC voltage tolerances. The P6SMB9.1A-E3/5B maintains this clamping performance with minimal degradation over 1000+ surge cycles when mounted per recommended pad layout.

Is the P6SMB9.1A-E3/5B suitable for automotive applications?

The P6SMB9.1A-E3/5B is RoHS-compliant and commercial-grade; however, it is not AEC-Q101 qualified. For automotive use, Vishay offers the P6SMB9.1AHE3_B variant (with "HE3" and "B" suffixes), which meets AEC-Q101 requirements. The P6SMB9.1A-E3/5B itself is intended for consumer, industrial, and telecom applications where automotive qualification is not mandated. Engineers selecting the P6SMB9.1A-E3/5B must confirm that their end equipment does not require AEC-Q101 certification, as the P6SMB9.1A-E3/5B lacks the extended temperature cycling, humidity, and lifetime validation required for under-hood deployment.

What does the "-E3/5B" suffix indicate in P6SMB9.1A-E3/5B?

The "-E3/5B" suffix in P6SMB9.1A-E3/5B specifies two key attributes: "E3" denotes RoHS-compliant, commercial-grade construction with matte tin-plated leads, and "5B" indicates packaging in a 13-inch diameter plastic tape-and-reel format containing 3200 units. This differs from "52", which uses a 7-inch reel with 750 units. The "E3" suffix also confirms compliance with JESD201 Class 2 whisker resistance and J-STD-002 solderability standards. The P6SMB9.1A-E3/5B is fully compatible with standard SMT pick-and-place equipment calibrated for SMB (DO-214AA) components.

How does the P6SMB9.1A-E3/5B compare to bidirectional TVS diodes like P6SMB9.1CA?

The P6SMB9.1A-E3/5B is unidirectional, meaning it conducts only during reverse-voltage transients and blocks forward current beyond its V_F (~3.5 V at 50 A). In contrast, P6SMB9.1CA is bidirectional and symmetrically clamps both polarities, making it suitable for AC lines or differential signals. The P6SMB9.1A-E3/5B offers lower leakage at V_WM (50 μA max) versus bidirectional versions (100 μA max for same V_WM), and its cathode band simplifies polarity-aware PCB layout. Use P6SMB9.1A-E3/5B for DC rails; choose P6SMB9.1CA only when protection is needed against both positive and negative transients on the same node.

What thermal derating applies to the P6SMB9.1A-E3/5B above 25 °C ambient?

The P6SMB9.1A-E3/5B follows a linear thermal derating curve starting at 25 °C ambient: its peak pulse power (P_PPM) decreases by approximately 0.6% per °C rise, based on R_θJA = 100 °C/W and T_J(max) = 150 °C. At 85 °C ambient, P_PPM is reduced to ~360 W; at 125 °C, it drops to ~180 W. Derating is defined in Figure 2 of the datasheet (Document Number 88370). To maintain full 600 W capability, ensure board layout uses the recommended 0.2" × 0.2" copper pads per terminal and avoid excessive local heating near the P6SMB9.1A-E3/5B.