Nexperia USA Inc. BZX79-C47,143

Overview

BZX79-C47,143 from Nexperia is a ±5% tolerance Zener voltage regulator diode with nominal 47 V breakdown voltage at 2 mA test current, 85 Ω typical differential resistance, and −1.4 mV/K temperature coefficient. It operates as a low-power voltage reference in biasing, regulation, and overvoltage protection circuits, rated for 500 mW total power dissipation at 50 °C ambient and housed in hermetically sealed SOD27 (DO-35) glass package.

For engineers reviewing the BZX79-C47,143 datasheet, BZX79-C47,143 pinout, BZX79-C47,143 application, or BZX79-C47,143 equivalent, key selection criteria include Zener voltage tolerance (±5%), thermal resistance (380 K/W), non-repetitive peak reverse power (40 W), and cathode-marked axial lead configuration - all critical for stable reference design in industrial power supplies and sensor conditioning circuits.

Technical Context

This discrete Zener diode functions exclusively in reverse-biased breakdown mode to maintain a stable DC reference voltage under varying load and temperature conditions. Its 47 V nominal Zener voltage is specified at I_Ztest = 2 mA, with 50 Ω to 170 Ω differential resistance across operating current range and a negative temperature coefficient of −1.4 mV/K - indicating decreasing voltage with rising junction temperature.

The device uses a hermetically sealed glass SOD27 (DO-35) package with axial leads and a cathode band marking. Thermal performance is defined by R_{th j-a} = 380 K/W (unmounted, max lead length) and R_{th j-tp} = 300 K/W (tie-point, 8 mm leads), limiting continuous operation to ≤500 mW at Tamb = 50 °C per absolute maximum ratings.

Key Specifications

Pinout & Package

Hermetically sealed axial-leaded SOD27 (DO-35) glass package with cathode identified by a colored band on the body. Leads are tinned copper-clad steel, suitable for through-hole PCB mounting and wave soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX79-C47,143, the 1N4750A offers greater power margin but sacrifices leakage performance and package reliability, while the BZX85-C47 trades hermetic stability for higher wattage - making the BZX79-C47,143 optimal for precision, long-life industrial references where size and environmental resilience matter.

Availability

BZX79-C47,143 is available at Aetrix Electronics and suitable for industrial power supplies, sensor signal conditioning, overvoltage protection circuits, and precision analog reference designs requiring stable component supply and long-term sourcing continuity.

Supply support for BZX79-C47,143 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-reliability diodes, MOSFETs, and logic devices for automotive and industrial markets.

The BZX79 series belongs to Nexperia's legacy Zener regulator portfolio, engineered for cost-effective, stable voltage referencing in low-power analog and power management circuits where hermetic reliability and tight parametric consistency are essential.

FAQ

What is the maximum continuous reverse current this diode can handle at 47 V?

The BZX79-C47,143 is not rated for continuous reverse current at full Zener voltage. At 47 V, its maximum continuous power dissipation is 500 mW, limiting sustained reverse current to approximately 10.6 mA (500 mW ÷ 47 V). Exceeding this risks thermal runaway due to its 380 K/W junction-to-ambient thermal resistance.

Does this part have a cathode marking, and how is it oriented on the PCB?

Yes - the cathode is marked by a distinct colored band near one end of the glass SOD27 body. During PCB layout, the banded end must connect to the higher-potential node (e.g., regulated rail), while the unmarked anode connects to ground or current-limiting resistor, ensuring proper reverse-bias operation.

Can BZX79-C47,143 replace BZX79-B47 in a circuit?

Yes, but with trade-offs: the 'C' version has ±5% tolerance versus ±2% for the 'B' variant, resulting in a wider 44–50 V Zener range. Differential resistance is also higher (85 Ω vs. 50 Ω typ), increasing output impedance. Use only where looser regulation and higher impedance are acceptable.

Is this diode suitable for use in automotive under-hood applications?

No - while its junction temperature range extends to +200 °C, the SOD27 glass package lacks AEC-Q200 qualification and is not rated for automotive vibration, thermal shock, or humidity cycling. Nexperia recommends automotive-grade alternatives like the BZX84-A47 series for qualified under-hood deployment.