onsemi P6SMB16AT3

Overview

P6SMB16AT3 from ON Semiconductor is a unidirectional 600 W peak power TVS diode designed to protect voltage-sensitive circuits from high-energy transients. It features a 13.6 V working peak reverse voltage (VRWM), 16 V breakdown voltage (VBR) at 1 mA test current, 22.5 V clamping voltage (VC) at 27 A peak pulse current, and sub-1 ns response time - deployed in automotive power supplies and industrial I/O interfaces.

For engineers reviewing the P6SMB16AT3 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping performance under 10/1000 µs surge, UL 497B certification for isolated loop protection, low leakage (<5 µA @ VRWM), and SMB package compatibility with automated SMT assembly.

Technical Context

The P6SMB16AT3 operates as a unidirectional Zener-based transient voltage suppressor, leveraging avalanche breakdown to clamp overvoltage events. Its design targets single-pulse 10/1000 µs waveforms up to 600 W, with thermal resistance of 226°C/W (junction-to-ambient) and 40°C/W (junction-to-lead) enabling robust surge handling at elevated ambient temperatures.

It exhibits low zener impedance and fast response (<1 ns typical), minimizing overshoot during transient suppression. The device is rated for −65°C to +150°C operating temperature and supports Pb-free reflow soldering at 260°C for 10 seconds - validated per JEDEC J-STD-020.

Key Specifications

Pinout & Package

Package: SMB (Case 403A), surface-mount, void-free thermosetting plastic with cathode polarity band. Leads are modified L-bend for enhanced pad adhesion and solderability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with P6SMB16AT3, SMBJ16A offers superior thermal performance for high-duty-cycle environments, while 1.5SMC16A trades compactness for higher single-event energy capacity - neither is pin-compatible without footprint revision.

Availability

P6SMB16AT3 is available at Aetrix Electronics and suitable for automotive power rail protection, industrial PLC I/O hardening, and medical equipment power supply safeguarding requiring stable component supply across multi-year production cycles.

Supply support for P6SMB16AT3 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

ON Semiconductor (now onsemi) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensors, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.

The P6SMB16AT3 belongs to the P6SMBxxAT3 series of unidirectional TVS diodes engineered for cost-effective, high-reliability transient suppression in space-constrained SMT designs - particularly targeting automotive and industrial control systems.

FAQ

What is the clamping voltage of the P6SMB16AT3 and how is it measured?

The P6SMB16AT3 has a maximum clamping voltage (VC) of 22.5 V, measured at a peak pulse current (IPP) of 27 A using a 10/1000 µs waveform. This value represents the upper limit of voltage seen by downstream circuitry during a standardized surge event - critical for ensuring protected ICs remain within absolute maximum ratings. The P6SMB16AT3 achieves this clamping performance while maintaining low leakage and fast response.

Is the P6SMB16AT3 RoHS compliant and what does the "G" suffix indicate?

Yes, the P6SMB16AT3G is RoHS compliant and Pb-free, as confirmed by ON Semiconductor's documentation and the "G" suffix in the part number. This designation indicates compliance with JEDEC J-STD-020 reflow profiles and qualifies the device for lead-free manufacturing processes, including peak solder temperatures up to 260°C for 10 seconds. The P6SMB16AT3G maintains identical electrical specifications to non-Pb-free variants.

Does the P6SMB16AT3 meet UL 497B requirements and why does that matter?

Yes, the P6SMB16AT3 is UL 497B recognized (File #E210057, Category QVGQ2) for isolated loop circuit protection - a requirement for many telecom, industrial, and medical applications. This certification validates performance in strike voltage breakdown, endurance conditioning, dielectric withstand, and discharge testing - far exceeding basic flammability standards. For designs requiring safety-agency approval, specifying P6SMB16AT3 satisfies critical compliance checkpoints.

What is the thermal resistance of the P6SMB16AT3 and how does it affect PCB layout?

The P6SMB16AT3 has a junction-to-ambient thermal resistance (R_JA) of 226°C/W on an FR-4 board with ON Semiconductor's recommended minimum footprint. This relatively high R_JA means effective heat dissipation relies heavily on copper area and via placement. To maintain reliability under repeated surges, designers should use ≥1 sq-in copper pads with ≥4 thermal vias per pad - especially important in automotive or industrial applications where ambient temperatures exceed 75°C.

Can the P6SMB16AT3 be used in bidirectional signal line protection?

No, the P6SMB16AT3 is strictly unidirectional and must not be used on bidirectional lines like USB, RS-485, or CAN without external circuitry. Its cathode-anode polarity is fixed, and reverse conduction only occurs during clamping - it does not conduct symmetrically. For bidirectional protection, ON Semiconductor specifies separate parts such as P6SMB16CAT3. Using P6SMB16AT3 on AC-coupled or differential signals risks improper clamping or device failure.