onsemi SZBZX84C30ET1G

Overview

SZBZX84C30ET1G from onsemi is a 30 V, 250 mW Zener voltage regulator diode in SOT-23 package, with nominal Zener voltage of 30 V at 5 mA test current, dynamic impedance of 80 Ω at 5 mA, and reverse leakage current ≤0.05 µA at 21 V, used for precision voltage reference and overvoltage protection in portable power rails.

For engineers reviewing the SZBZX84C30ET1G datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage tolerance (±2 V), temperature coefficient (+24.4 mV/°C), low capacitance (70 pF), AEC-Q101 qualification, and Pb-free RoHS compliance.

Technical Context

This device operates as a two-terminal shunt regulator, maintaining stable output voltage across varying load currents by conducting excess current to ground when input exceeds its Zener breakdown threshold. It features a cathode-anode polarity configuration with Pin 1 = Anode, Pin 2 = No Connection, Pin 3 = Cathode.

Designed for surface-mount assembly on FR-5 or alumina substrates, it delivers 250 mW total power dissipation at 25 °C ambient, derating linearly above that temperature, and withstands 225 W nonrepetitive peak pulse power per 8 × 20 µs waveform per Figure 9.

Key Specifications

Pinout & Package

SOT-23 (TO-236) surface-mount plastic package, void-free thermosetting case, corrosion-resistant finish, UL 94 V-0 flammability rating, 2.90 mm × 1.30 mm × 1.00 mm outline, 1.90 mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SZBZX84C30ET1G, BZX84C30ET1G offers identical regulation performance without automotive validation, while MMSZ5261ET1G trades smaller size for higher power and relaxed impedance-making SZBZX84C30ET1G optimal for space-constrained, AEC-Q101–compliant 30 V reference designs.

Availability

SZBZX84C30ET1G is available at Aetrix Electronics and suitable for automotive body control modules, portable medical wearables, industrial PLC input conditioning, and USB power rail protection requiring stable component supply with full traceability and lifecycle management.

Supply support for SZBZX84C30ET1G 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 is a global semiconductor supplier delivering energy-efficient silicon solutions for automotive, industrial, cloud, medical, and IoT applications, with focus on sustainable innovation and functional safety.

SZBZX84C30ET1G belongs to the BZX84CxxxET1G/SZBZX84CxxxET1G series of Zener regulators designed specifically for high-density, automotive-qualified voltage reference and overvoltage protection in space-limited portable and embedded systems.

FAQ

What is the Zener voltage tolerance of SZBZX84C30ET1G at 5 mA test current?

The SZBZX84C30ET1G has a Zener voltage range of 28 V to 32 V at I_ZT = 5 mA, corresponding to a ±2 V absolute tolerance. This specification is confirmed in the Electrical Characteristics table on page 3 of the official onsemi datasheet, where V_Z1 (min/nom/max) is listed as 28/30/32 V under the SZBZX84C30ET1G row. The tolerance reflects process variation and ensures predictable clamping behavior in production designs.

Is SZBZX84C30ET1G pin-compatible with standard BZX84C30ET1G?

Yes, SZBZX84C30ET1G shares identical pinout (Pin 1 = Anode, Pin 2 = No Connection, Pin 3 = Cathode), package dimensions (SOT-23), and marking layout with BZX84C30ET1G. The "SZ" prefix denotes automotive qualification (AEC-Q101) and PPAP capability, but mechanical and electrical interface compatibility is maintained per onsemi's package style 8 definition in the mechanical drawings.

What is the maximum allowable junction temperature for SZBZX84C30ET1G?

The junction and storage temperature range for SZBZX84C30ET1G is −65 °C to +150 °C, as specified in the Maximum Ratings table on page 1 of the datasheet. This limit applies under all operating conditions, and exceeding +150 °C risks permanent parametric shift or catastrophic failure. Thermal design must ensure R_JA = 500 °C/W (FR-5 board) or 417 °C/W (alumina substrate) does not result in T_J > 150 °C at worst-case ambient and power dissipation.

Does SZBZX84C30ET1G support reflow soldering, and what is the peak profile limit?

Yes, SZBZX84C30ET1G supports standard Pb-free reflow soldering per JEDEC J-STD-020. The maximum case temperature is rated at 260 °C for 10 seconds, consistent with IPC/JEDEC Level 3 moisture sensitivity. The device is classified as MSL-1 (unlimited floor life) and requires no pre-bake prior to reflow, provided packaging remains sealed and humidity exposure is controlled.

How does the temperature coefficient of SZBZX84C30ET1G affect voltage stability over automotive temperature ranges?

The SZBZX84C30ET1G exhibits a positive temperature coefficient of +24.4 mV/°C at I_ZT = 5 mA, meaning its Zener voltage increases linearly with temperature. Over the automotive range (−40 °C to +125 °C), this results in a total drift of approximately +4.0 V - from ~27.5 V at −40 °C to ~31.5 V at +125 °C - which must be accounted for in precision reference designs using SZBZX84C30ET1G.