Nexperia USA Inc. BZT5250H-C51X

Overview

BZT5250H-C51X from Nexperia is a low-current Zener diode in SOD123F package, rated for 51 V nominal Zener voltage at 50 µA test current, with ±5 % tolerance, 830 mW total power dissipation, and optimized leakage behavior for noise-sensitive regulation in portable battery-powered systems.

For engineers reviewing the BZT5250H-C51X datasheet, BZT5250H-C51X pinout, BZT5250H-C51X application, or BZT5250H-C51X equivalent, this part serves as a precision low-bias voltage reference in power rail monitoring, analog sensor biasing, and microcontroller reset circuitry where stable reverse breakdown at minimal quiescent current is required.

Technical Context

This Zener diode operates in reverse breakdown mode with a specified V_Z = 50.0–52.0 V at I_Z = 50 µA, exhibiting a temperature coefficient of +0.05 mV/K and differential resistance of 400 Ω at I_Z = 2 mA. Its intentional minor leakage rise improves switching transients and reduces high-frequency noise in regulation paths.

Designed for surface-mount use on FR4 PCBs with single-sided copper, it delivers thermal resistance R_th(j-a) = 330 K/W (free air) and R_th(j-sp) = 70 K/W (cathode solder point), enabling reliable operation up to T_j = 150 °C and ambient range of −55 to +150 °C.

Key Specifications

Pinout & Package

The BZT5250H-C51X is housed in a compact SOD123F surface-mount plastic package (2.6 mm × 1.6 mm × 1.1 mm), featuring flat leads and cathode-side marking bar for polarity identification.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C51 and MMSZ5257B, the BZT5250H-C51X delivers superior thermal resistance (70 K/W vs. >100 K/W), tighter low-current regulation stability, and purpose-built leakage characteristics for noise-critical portable applications - making it the preferred choice where precision, low bias, and EMI performance intersect.

Availability

BZT5250H-C51X is available at Aetrix Electronics and suitable for power rail monitoring, analog sensor biasing, microcontroller reset circuitry, and portable battery protection requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for BZT5250H-C51X 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, with leadership in automotive-qualified and industrial-grade components.

The BZT5250H series belongs to Nexperia's low-current Zener portfolio, engineered specifically for stable voltage reference and regulation in battery-constrained, noise-sensitive, and space-limited applications - not general-purpose clamping.

FAQ

What is the exact Zener voltage tolerance for BZT5250H-C51X?

The BZT5250H-C51X has a guaranteed Zener voltage range of 50.0 V to 52.0 V at I_Z = 50 µA, corresponding to the ±5 % tolerance denoted by the "C" prefix in its marking code. This is verified per Table 8 and Table 9 of the official Nexperia datasheet Rev. 1 (18 July 2024), and applies across the full operating temperature range of −55 °C to +150 °C.

Can BZT5250H-C51X be used in place of a standard 51 V Zener like BZX84-C51?

Yes, but with design considerations: BZT5250H-C51X shares identical voltage rating and tolerance, yet offers lower thermal resistance (70 K/W vs. ~200 K/W), optimized leakage for noise reduction (per AN90031), and SOD123F footprint. It is not a drop-in replacement due to different package dimensions and thermal layout requirements, but provides measurable advantages in low-noise, thermally constrained, or high-reliability applications.

What is the maximum continuous reverse current before breakdown onset?

At V_R = 38 V (75 % of nominal V_Z), the reverse current is guaranteed ≤ 0.05 µA per datasheet Table 9. This ultra-low leakage ensures minimal loading on upstream sources and preserves accuracy in high-impedance reference dividers, especially critical in battery-powered systems where standby current must remain sub-100 nA.

Does BZT5250H-C51X require derating above 25 °C ambient?

Yes - total power dissipation must be linearly derated above 25 °C ambient at 6.6 mW/°C, based on the 830 mW rating at T_amb ≤ 25 °C and R_th(j-a) = 330 K/W. For example, at 75 °C ambient, maximum allowable P_tot is reduced to 500 mW. Derating follows the curve in Figure 1 of the datasheet and is mandatory to avoid junction temperature exceeding 150 °C.