Diodes Incorporated BZT52C39S-7-F

Overview

BZT52C39S-7-F from Diodes Incorporated is a surface-mount Zener diode with nominal 39 V zener voltage (37–41 V range at 2 mA), 200 mW power dissipation, and SOD323 package. It provides precision voltage regulation in low-power biasing, overvoltage protection, and reference circuits for industrial sensors and automotive ECUs.

For engineers reviewing the BZT52C39S-7-F datasheet, BZT52C39S-7-F pinout, BZT52C39S-7-F application, or BZT52C39S-7-F equivalent, key selection criteria include zener voltage tolerance (±5.1%), dynamic impedance (130 Ω at 2 mA), temperature coefficient (+27.3 to +33.4 mV/°C), 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, while the SOD323 package supports high-density PCB layouts and automated reflow assembly.

The device exhibits a positive temperature coefficient (+27.3 to +33.4 mV/°C) above ~6 V, enabling predictable thermal drift in voltage references. With 0.1 µA maximum reverse leakage at 30 V and 130 Ω zener impedance at 2 mA, it delivers tight regulation for low-current sensing and feedback paths.

Key Specifications

Pinout & Package

Package: SOD323 - ultra-small plastic surface-mount case with cathode band marking; dimensions: 1.30 mm (D) × 1.70 mm (E) × 0.30 mm (L); weight ≈ 0.0049 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ5267BT1G and BZX84-C39, BZT52C39S-7-F offers the smallest footprint (SOD323), AEC-Q101 qualification, and optimized thermal resistance (625 °C/W) for compact automotive PCBs-making it ideal where space, reliability, and regulatory compliance are jointly constrained.

Availability

BZT52C39S-7-F is available at Aetrix Electronics and suitable for industrial sensor conditioning, automotive body control modules, and PLC input protection requiring stable component supply and long-term lifecycle support.

Supply support for BZT52C39S-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 and manufacturing operations across Asia and the Americas.

The BZT52C series belongs to Diodes' precision Zener diode product line, engineered specifically for voltage regulation and protection in space-constrained, high-reliability applications including automotive, industrial automation, and medical electronics.

FAQ

What is the maximum reverse voltage (V_R) that BZT52C39S-7-F can withstand without breakdown?

The device does not specify a distinct "maximum reverse voltage" rating. Instead, it begins controlled breakdown at its nominal zener voltage (39 V) with a tolerance of ±5.1%. At 30 V reverse bias, leakage current is guaranteed ≤0.1 µA; operation above 41 V risks exceeding the 200 mW power limit unless current is strictly limited by external series resistance.

Is BZT52C39S-7-F suitable for use in high-frequency signal path applications?

No-it is not designed for RF or high-speed signal routing. Its typical total capacitance is ~1.5 pF at 1 V reverse bias (inferred from Fig. 4 trend for 39 V devices), but it lacks specified frequency response or switching speed parameters. Use only in DC/low-frequency bias, regulation, or protection roles-not as a signal diode or RF clamp.

How does the temperature coefficient affect voltage regulation accuracy over temperature?

With a TC of +27.3 to +33.4 mV/°C, the zener voltage increases linearly with junction temperature. Over a –40°C to +125°C range, this causes a total shift of +4.3 to +5.5 V. For precision references, this must be compensated via circuit design (e.g., complementary TC components) or limited to narrow ambient ranges where drift remains within system tolerance.

Can BZT52C39S-7-F be used in parallel to increase power handling?

No-zener diodes should not be paralleled without individual ballasting resistors due to mismatched breakdown voltages. Even with matched units, thermal runaway risk remains because higher-current devices heat more, lowering their zener voltage and attracting disproportionate current. Use a single higher-power device (e.g., MMSZ5267BT1G) instead.