Taiwan Semiconductor Corporation BZV55C3V9

Overview

BZV55C3V9 from Taiwan Semiconductor is a surface-mount Zener diode with nominal zener voltage 3.9 V, ±5% tolerance, 500 mW power dissipation, and 5 mA test current; it provides precise low-voltage regulation in compact DC/DC converter feedback paths and adapter reference circuits.

For engineers reviewing the BZV55C3V9 datasheet, BZV55C3V9 pinout, BZV55C3V9 application, or BZV55C3V9 equivalent, key selection criteria include zener voltage accuracy at 5 mA, dynamic impedance of 85 Ω at IZT, leakage current ≤2 µA at 1.0 V reverse bias, and MMELF package compatibility with high-density SMT layouts.

Technical Context

The BZV55C3V9 operates as a single-die, hermetically sealed glass Zener diode optimized for stable voltage reference and low-power stabilization. Its 3.7–4.1 V zener range (min–max) and 85 Ω dynamic impedance at 5 mA support tight regulation in space-constrained linear regulators and sensing front-ends.

Designed for ambient operation up to +175 °C junction temperature, it features matte tin-plated leads compliant with J-STD-002 solderability and cathode band polarity marking. Thermal resistance is 300 °C/W junction-to-ambient, limiting continuous power handling under natural convection.

Key Specifications

Pinout & Package

Package: MMELF - miniature metal electrode leadless face, axial lead configuration with cathode band marking; dimensions: 3.50 ± 0.20 mm length, Ø1.50 ± 0.10 mm diameter, 0.35 ± 0.15 mm lead diameter.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX55C3V9 and BZX584C3V9, the BZV55C3V9 offers optimal balance of MMELF SMT compatibility, 500 mW thermal capability, and 85 Ω dynamic impedance-making it preferred for industrial DC/DC feedback loops requiring both density and reliability.

Availability

BZV55C3V9 is available at Aetrix Electronics and suitable for low-voltage stabilizers, on-board DC/DC converters, and AC/DC adapters requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for BZV55C3V9 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

Taiwan Semiconductor Corporation (TSC) is a vertically integrated semiconductor manufacturer specializing in discrete power devices, rectifiers, Zener diodes, and TVS components for industrial and consumer markets.

The BZV55 series was developed specifically for high-reliability, surface-mount voltage reference and stabilization in compact power conversion systems where hermetic sealing and tight V_Z tolerance are critical.

FAQ

What is the zener voltage tolerance and test condition for BZV55C3V9?

The BZV55C3V9 has a nominal zener voltage of 3.9 V with a guaranteed tolerance of ±5%, tested at I_ZT = 5 mA under pulse conditions (30 ms duration). The actual measured V_Z falls between 3.7 V and 4.1 V, making it suitable for precision reference applications where tight regulation is required without external trimming.

What package type does BZV55C3V9 use and what are its key mechanical dimensions?

BZV55C3V9 uses the MMELF package (JEDEC DO-213AA variant), featuring a 3.50 ± 0.20 mm body length, Ø1.50 ± 0.10 mm diameter, and cathode band polarity marking. Its axial lead configuration and compact size enable high-density placement in space-constrained SMT designs, especially in DC/DC converter feedback networks.

How does the dynamic impedance of BZV55C3V9 affect its regulation performance?

The BZV55C3V9 exhibits a dynamic impedance (Z_ZT) of 85 Ω at I_ZT = 5 mA, directly impacting its ability to maintain stable output voltage under varying load currents. Lower Z_ZT yields tighter regulation-this value ensures <±10 mV deviation for ±0.5 mA load shifts, critical for accurate feedback in switching regulators.

Is BZV55C3V9 suitable for high-temperature environments like automotive under-hood applications?

Yes, BZV55C3V9 supports a junction temperature range of –65 °C to +175 °C and is rated for continuous operation at full 500 mW power dissipation up to +25 °C ambient. With R_θJA = 300 °C/W, derating is required above 25 °C-but its glass-sealed construction and wide T_J range make it viable for under-hood sensor power supplies with proper thermal design.

What is the maximum leakage current specification for BZV55C3V9 and at what reverse voltage is it measured?

The BZV55C3V9 specifies a maximum leakage current (I_R) of 2 µA at a reverse voltage (V_R) of 1.0 V. This low leakage ensures minimal error injection into high-impedance reference nodes-such as those found in precision op-amp biasing or ADC voltage dividers-preserving system-level accuracy without additional filtering.