Nexperia USA Inc. BZX79-B3V0,133

Overview

BZX79-B3V0,133 from Nexperia is a ±2% tolerance Zener voltage regulator diode in DO-35 (SOD27) glass package, designed for low-power voltage reference and stabilization at 3.0 V nominal Zener voltage with 5 mA test current, 325 Ω typical differential resistance, and −2.1 mV/K temperature coefficient - used in precision analog sensor biasing and microcontroller reset circuitry.

For engineers reviewing the BZX79-B3V0,133 datasheet, BZX79-B3V0,133 pinout, BZX79-B3V0,133 application, or BZX79-B3V0,133 equivalent, this page delivers verified electrical parameters, thermal behavior, cathode-marked axial lead configuration, and direct-fit alternatives for low-voltage reference design in industrial control and portable electronics.

Technical Context

This Zener diode operates in reverse breakdown mode with a nominal Zener voltage of 3.0 V at I_Z = 5 mA, exhibiting a tight ±2% tolerance (2.94–3.06 V), low dynamic impedance (325 Ω typ., 600 Ω max.), and negative temperature coefficient (−3.5 to −2.1 mV/K) optimized for stable low-voltage regulation below 5 V.

It is rated for 500 mW total power dissipation at T_amb = 50 °C (with 8 mm lead length), supports non-repetitive peak reverse power up to 40 W (100 μs pulse), and features 10 μA maximum reverse leakage at V_R = 1 V - confirming suitability for standby-biased reference nodes requiring low quiescent current.

Key Specifications

Pinout & Package

DO-35 (SOD27) axial-leaded glass package with cathode identified by a single dark band on the body; leads are tinned copper-clad steel, suitable for wave or hand soldering. Thermal resistance R_{th j-a} = 380 K/W (unmounted, max. lead length).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX79-B3V0,133, MMBZ5226BS-7-F trades through-hole reliability and power handling for SMT scalability, while BZX55C3V0 sacrifices precision for broader availability and lower unit cost - making the B-series optimal for accuracy-critical 3.0 V references.

Availability

BZX79-B3V0,133 is available at Aetrix Electronics and suitable for microcontroller reset circuits, ADC reference stabilization, and sensor biasing networks requiring stable component supply and long-lifecycle support.

Supply support for BZX79-B3V0,133 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

Nexperia is a global leader in discrete semiconductors, formed in 2017 from the former NXP Standard Products division, specializing in high-volume, high-reliability components for automotive, industrial, and consumer markets.

The BZX79 series belongs to Nexperia's legacy Zener diode portfolio, engineered specifically for low-power voltage regulation and reference applications where precision, thermal stability, and long-term parametric consistency are essential.

FAQ

What is the maximum continuous reverse current this diode can handle at 3.0 V?

The BZX79-B3V0,133 does not specify a maximum continuous reverse current at its Zener voltage; instead, it is characterized by Zener test current (I_Z = 5 mA) and total power dissipation limit (500 mW at T_amb = 50 °C). At 3.0 V, this corresponds to ~167 mA absolute maximum steady-state reverse current before exceeding P_tot, though practical operation stays well below that to maintain regulation accuracy and thermal safety.

Is the cathode marked on the physical device, and how is polarity confirmed?

Yes - the cathode is unambiguously marked by a single dark band on the glass body of the DO-35 package. When oriented with the band facing left, the left lead is cathode and the right lead is anode. This marking conforms to JEDEC DO-35 standard and is visible under 10× magnification; no multimeter diode test is needed for polarity verification during manual assembly.

How does the −2.1 mV/K temperature coefficient affect circuit performance at 85 °C?

At 85 °C ambient (ΔT = +60 K from 25 °C), the Zener voltage shifts by approximately −126 mV (−2.1 mV/K × 60 K), resulting in a regulated output of ~2.87 V. This predictable drift is leveraged in compensated reference designs; for uncompensated uses, it introduces ~4.2% error - acceptable in many non-precision biasing roles but insufficient for 12-bit ADC references without calibration.

Can this diode be used in parallel for higher current capability?

No - Zener diodes exhibit manufacturing variations in V_Z and r_diff, causing current hogging when paralleled. Even matched units from same wafer lot show >5% V_Z spread, leading to thermal runaway in one device. For higher current, use a single higher-power Zener (e.g., BZX85 series) or add an external pass transistor; parallel connection is not recommended or characterized in the datasheet.