onsemi MMBZ27VCWT1G

Overview

MMBZ27VCWT1G from onsemi is a dual common-cathode Zener diode TVS device in SC−70 (SOT−323) package, rated for 40 W peak pulse power at 1.0 ms, 27 V nominal Zener breakdown voltage, and 22 V working peak reverse voltage, designed for bidirectional transient voltage suppression in space-constrained ESD protection circuits such as automotive Single-Wire CAN networks.

For engineers reviewing the MMBZ27VCWT1G datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage (38 V @ 1.0 A), low leakage (<100 nA @ 22 V), AEC−Q101 qualification, UL 94 V−0 flammability rating, and dual-line protection capability in a single 3-pin surface-mount package.

Technical Context

This dual Zener TVS uses a monolithic silicon structure with two anodes sharing one cathode (Pin 1 = ANODE, Pin 2 = ANODE, Pin 3 = CATHODE), enabling either two independent unidirectional protection paths (Pins 1–3 and Pins 2–3) or a single bidirectional configuration (Pins 1–2 across Pin 3). Its thermal resistance is 618°C/W, and junction temperature range spans −55°C to +150°C.

The device delivers 38 V clamping voltage at 1.0 A peak pulse current per Figure 4 waveform, supports ESD immunity exceeding 16 kV HBM, and maintains stable breakdown voltage with ±0.026%/°C temperature coefficient - critical for robust operation across automotive ambient ranges.

Key Specifications

Pinout & Package

SC−70 (SOT−323) package: void-free thermosetting plastic case, Pb−Free/RoHS compliant, UL 94 V−0 rated, solderable at 260°C for 10 seconds.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ27VCWT1G, SZMMBZ27VCWT1G adds documented automotive process controls without altering electrical behavior, while MMBZ27VCWT3G offers identical protection in higher-reel packaging - both serve as direct form-fit-function alternatives in design reuse or procurement scaling.

Availability

MMBZ27VCWT1G is available at Aetrix Electronics and suitable for automotive ECU designs, industrial sensor interfaces, medical signal conditioning circuits, and consumer USB port protection requiring stable component supply and long-term lifecycle assurance.

Supply support for MMBZ27VCWT1G 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 power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and IoT applications.

The MMBZ27VCW series belongs to onsemi's transient voltage suppression portfolio, engineered specifically for high-reliability, space-constrained ESD and surge protection in automotive and medical systems demanding AEC−Q101 qualification and UL 94 V−0 compliance.

FAQ

What is the clamping voltage of MMBZ27VCWT1G and how is it measured?

The MMBZ27VCWT1G has a maximum clamping voltage of 38 V at 1.0 A peak pulse current (IPP), measured using the standardized 1.0 ms exponential waveform defined in Figure 4 of its datasheet. This value represents the upper voltage limit imposed on protected lines during transient events, ensuring downstream ICs remain within safe operating margins. The MMBZ27VCWT1G achieves this clamping performance consistently across its specified temperature range of −55°C to +150°C.

Is MMBZ27VCWT1G suitable for automotive applications?

Yes, MMBZ27VCWT1G is qualified to AEC−Q101 standards and supports PPAP documentation, making it suitable for automotive applications including Single-Wire CAN networks, infotainment interfaces, and body control modules. Its UL 94 V−0 flammability rating, −55°C to +150°C operating range, and 16 kV HBM ESD rating meet stringent automotive reliability requirements. The MMBZ27VCWT1G is explicitly referenced in SAE J2411 for ECU-level transient protection.

How does the dual common-cathode configuration of MMBZ27VCWT1G benefit circuit design?

The dual common-cathode configuration of MMBZ27VCWT1G allows two independent signal lines to share a single ground-referenced protection path, reducing component count and PCB area versus discrete Zeners. Pins 1 and 2 serve as separate anodes tied to distinct lines, while Pin 3 acts as the shared cathode to system ground - enabling compact dual-line protection in applications like differential buses or redundant sensor inputs. This architecture is electrically equivalent to dual common-anode layouts per the datasheet.

What is the maximum working peak reverse voltage for MMBZ27VCWT1G?

The maximum working peak reverse voltage (VRWM) for MMBZ27VCWT1G is 22 V, meaning it can continuously block up to 22 V in reverse bias without significant leakage current. At this voltage, reverse leakage remains below 50 nA (typical) and <100 nA (max), preserving signal integrity in high-impedance circuits. Exceeding VRWM risks premature conduction and increased power dissipation, so MMBZ27VCWT1G is selected for systems where normal operating voltage stays safely below 22 V.

Does MMBZ27VCWT1G support bidirectional transient suppression?

Yes, MMBZ27VCWT1G supports bidirectional transient suppression when configured with Pins 1 and 2 as inputs and Pin 3 as the common cathode reference - effectively forming two back-to-back Zener diodes. In this arrangement, it clamps positive transients on either anode to ~27 V above ground and negative transients to ~27 V below ground, achieving symmetrical ±38 V clamping at 1.0 A. This eliminates the need for separate TVS devices on differential signal pairs.