Nexperia USA Inc. NZX33C,133

Overview

NZX33C,133 from Nexperia is a single Zener diode in a hermetically sealed SOD27 (SC-40) glass package, designed for precision voltage regulation at 33 V nominal Zener voltage with ±5% tolerance (31.4–34.5 V), 120 Ω differential resistance at I_Z = 2 mA, and ≤0.05 µA reverse leakage current. It delivers stable reference performance in low-power analog circuits, power supply feedback loops, and overvoltage protection stages.

For engineers reviewing the NZX33C,133 datasheet, NZX33C,133 pinout, NZX33C,133 application, or NZX33C,133 equivalent, this device supports design validation of 33 V clamping thresholds, thermal-aware PCB layout on FR4 without metallization pad, and selection of axial-leaded Zener diodes with verified 175 °C junction temperature rating and 380 K/W junction-to-ambient thermal resistance.

Technical Context

This Zener diode operates in reverse breakdown mode with a specified working voltage of 33 V at I_Z = 2 mA, exhibiting a temperature coefficient near zero in its mid-voltage range and optimized for stable DC reference generation. Its low differential resistance (120 Ω) ensures minimal output voltage variation under load changes.

The device uses a hermetically sealed glass package (SOD27/SC-40) with axial leads, enabling reliable long-term operation in ambient temperatures from −65 °C to +175 °C and storage up to +175 °C. Thermal resistance values-R_th(j-a) = 380 K/W and R_th(j-t) = 300 K/W-are measured on standard FR4 PCB with 8 mm max lead length.

Key Specifications

Pinout & Package

Package: SOD27 (SC-40), hermetically sealed axial-leaded glass package with cathode band marking. Dimensions: 4.25 mm max length, 1.85 mm max diameter, 25.4 mm min lead spacing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX55-C33 and 1N4749A, NZX33C,133 offers superior thermal performance (380 vs. 500 K/W), lower leakage (0.05 vs. 1 µA), and optimal 2 mA test current alignment with modern ultra-low-power analog signal chains.

Availability

NZX33C,133 is available at Aetrix Electronics and suitable for industrial sensor conditioning, PLC input protection, low-power battery management, and automotive aftermarket diagnostic interfaces requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for NZX33C,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 semiconductor expert focused on high-volume, high-reliability discrete and logic devices, serving automotive, industrial, and consumer markets with rigorous quality standards and AEC-Q200 qualified components.

The NZX series targets general-purpose Zener regulation with hermetic reliability, delivering stable voltage references across extreme ambient conditions using axial-leaded glass packages optimized for manual and automated through-hole assembly.

FAQ

What is the maximum continuous reverse current the NZX33C,133 can sustain without degradation?

The device supports up to 15.2 mA continuous reverse current at 33 V (500 mW / 33 V) within its 500 mW total power dissipation limit at T_tp ≤25 °C. Derating is required above 25 °C ambient per the 380 K/W thermal resistance curve; at 70 °C ambient, max sustainable current drops to ~10.5 mA to maintain T_j ≤175 °C.

How does the cathode band marking align with industry-standard polarity conventions?

The black band on the SOD27 package marks Pin 1 (cathode), consistent with JEDEC SC-40 and IEC 60747-2 standards. When installed, the banded end connects to the higher-potential node (e.g., regulated output or surge source), while the unbanded anode connects to ground or return path-ensuring proper reverse-bias operation during regulation or clamping.

Can NZX33C,133 be used in place of a 33 V TVS diode for ESD protection?

No-it is not rated for IEC 61000-4-2 ESD events. As a Zener diode, it lacks the fast response (<1 ns) and high peak pulse power capability of dedicated TVS devices. Use only for steady-state voltage regulation or slow transients; pair with a TVS (e.g., PESD3V3L1UB) for combined DC reference + ESD protection.

What PCB layout practices optimize thermal performance for NZX33C,133 on FR4?

Keep leads ≤8 mm long and avoid solder mask over copper near the diode body. Use minimum 25 mm² of 1 oz copper pour connected to both leads to reduce R_th(j-a) by ~30%. Do not use thermal relief on pads-solid connections maximize heat conduction from the glass package into the board.