Diodes Incorporated BZT52C51S-7

Overview

BZT52C51S from Diodes Incorporated is a surface-mount Zener diode with nominal zener voltage 51 V, ±6% tolerance (48–54 V), 200 mW power dissipation, and 100 Ω dynamic impedance at 5 mA test current; used for precision voltage regulation and overvoltage protection in low-power analog sensor interfaces and power supply feedback loops.

For engineers reviewing the BZT52C51S datasheet, BZT52C51S pinout, BZT52C51S application, or BZT52C51S equivalent, key selection criteria include zener voltage accuracy at 5 mA, thermal resistance (833 °C/W), SOD-323 package footprint compatibility, reverse leakage (<0.1 µA @ 38 V), and RoHS-compliant matte tin terminations.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable reference voltage under varying load and temperature conditions. It features planar die construction for consistent parametric performance and low capacitance (≈10 pF @ 1 V, 1 MHz) suitable for moderate-frequency regulation.

Designed for automated SMT assembly, it meets J-STD-020 Level 1 moisture sensitivity and uses green molding compound (UL 94V-0). Its thermal resistance of 833 °C/W limits continuous power dissipation to 200 mW at 25°C ambient, derating linearly above that point.

Key Specifications

Pinout & Package

Package: SOD-323 - ultra-small plastic surface-mount case (2.4 mm × 1.35 mm × 0.9 mm), lead-free, RoHS-compliant, UL 94V-0 rated.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5251BS-7-F and BZX84-C51, the BZT52C51S offers optimal balance of compact size, 200 mW capability, and 100 Ω regulation stiffness-making it preferred for space-constrained, low-current reference designs where thermal mass is limited.

Availability

BZT52C51S is available at Aetrix Electronics and suitable for industrial sensor signal conditioning, USB-C power delivery feedback, and low-power IoT node regulators requiring stable component supply with guaranteed traceability and lifecycle continuity.

Supply support for BZT52C51S 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability, energy-efficient components for industrial, computing, and consumer markets.

The BZT52 series belongs to Diodes' general-purpose Zener diode product line, engineered for cost-effective, high-yield voltage reference and protection in automated SMT production environments.

FAQ

What is the maximum reverse voltage before breakdown for BZT52C51S?

The BZT52C51S begins controlled reverse breakdown at a nominal 51 V, with guaranteed minimum 48 V and maximum 54 V at 5 mA test current (I_ZT). Below 38 V, reverse leakage remains ≤0.1 µA - confirming no significant conduction occurs prior to the specified zener knee.

Can BZT52C51S be used in place of a 5.1 V Zener diode?

No - the BZT52C51S is a 51 V device, not 5.1 V. Using it as a 5.1 V substitute would result in catastrophic failure or no regulation. The "C51" suffix denotes 51 V; 5.1 V variants in the same family are marked BZT52C5V1S and have distinct electrical characteristics.

Is the SOD-323 package hand-solderable?

Yes, the SOD-323 package is hand-solderable using fine-tip irons and flux, though its 0.9 mm height and 0.65 mm pitch require careful thermal control. Diodes Incorporated confirms compatibility with standard reflow profiles (J-STD-020 Level 1), and the matte tin finish ensures reliable wetting without lead-based solder.

Does BZT52C51S have a specified zener temperature coefficient?

The datasheet does not publish a numeric zener temperature coefficient (tempco), but Figure 2 shows stable breakdown behavior from −65°C to +150°C, and the planar die construction implies typical tempco of ±0.05%/°C - sufficient for non-critical references. For precision applications, a dedicated temperature-compensated reference IC is recommended.