Diodes Incorporated BZT52C20S-7-F

Overview

BZT52C20S-7-F from Diodes Incorporated is a surface-mount Zener diode with nominal 20 V zener voltage (18.8–21.2 V range at 5 mA), 200 mW power dissipation, and SOD323 package. It provides precise voltage regulation in low-power biasing, reference, and overvoltage protection circuits for industrial sensors and automotive ECUs.

For engineers reviewing the BZT52C20S-7-F datasheet, BZT52C20S-7-F pinout, BZT52C20S-7-F application, or BZT52C20S-7-F equivalent, key selection criteria include zener voltage tolerance (±6%), dynamic impedance (55 Ω @ 5 mA), temperature coefficient (+14.0 mV/°C), reverse leakage (<0.1 µA @ 14.4 V), and AEC-Q101 qualification for automotive use.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage across its terminals under varying current loads. Its planar die construction ensures consistent breakdown characteristics and low noise, while the SOD323 package supports high-density PCB layouts and automated reflow assembly.

The device exhibits a positive temperature coefficient of +14.0 mV/°C above 6 V, enabling predictable thermal drift compensation in reference designs. Its 200 mW power rating and 625 °C/W junction-to-ambient thermal resistance define safe operating limits under standard FR-4 board mounting conditions.

Key Specifications

Pinout & Package

Package: SOD323 - ultra-compact plastic-molded case (1.30 mm × 1.70 mm × 0.90 mm), matte tin-plated alloy 42 leadframe, cathode band marking, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ5249B-7-F and BZX84-C20, BZT52C20S-7-F offers the smallest footprint (SOD323), automotive qualification, and optimal balance of regulation precision and thermal performance for space-constrained ECU and sensor modules.

Availability

BZT52C20S-7-F is available at Aetrix Electronics and suitable for automotive engine control units, industrial sensor interfaces, and medical diagnostic equipment requiring stable component supply and long-term lifecycle continuity.

Supply support for BZT52C20S-7-F 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, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The BZT52 series belongs to Diodes' automotive-qualified Zener diode product line, engineered specifically for precision voltage reference and overvoltage protection in harsh-environment electronics where reliability and parametric consistency are critical.

FAQ

What is the maximum reverse voltage this Zener can withstand before breakdown?

The BZT52C20S-7-F has a nominal zener voltage of 20 V, with a guaranteed breakdown range of 18.8 V to 21.2 V at 5 mA test current. It is not rated for sustained reverse voltage above 21.2 V; operation beyond this risks irreversible avalanche degradation. The device is designed for controlled reverse-bias regulation, not blocking.

Is this part suitable for use in high-frequency signal clamping applications?

No - the BZT52C20S-7-F is optimized for DC and low-frequency voltage regulation, not RF clamping. Its typical capacitance is ~12 pF at 1 V reverse bias, and it lacks specified switching speed or transient response data. For signal clamping above 1 MHz, TVS diodes like D1213A-02SO or ESD-rated Schottky arrays are recommended.

How does the +14.0 mV/°C temperature coefficient affect circuit design?

The positive temperature coefficient means the zener voltage increases by 14.0 mV per °C rise in junction temperature. In precision references, this requires thermal compensation (e.g., pairing with negative-TC components) or operating within a narrow ambient range. At +125°C, V_Z rises ~1.4 V above its 25°C value - a critical factor in high-temperature automotive applications.

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

No - Zener diodes must not be paralleled without individual current-limiting resistors due to mismatched V_Z tolerances (±6%). Even with matched units, thermal runaway occurs because the lower-V_Z unit draws disproportionate current and self-heats, further lowering its V_Z. For higher current, select a single higher-power Zener or use active regulation.