Taiwan Semiconductor Corporation BZX585B4V7

Overview

BZX585B4V7 from Taiwan Semiconductor is a surface-mount Zener diode with nominal zener voltage 4.7 V ±2%, 200 mW power dissipation, 80 Ω dynamic impedance at 5 mA test current, and SOD-523F package. It provides precise voltage regulation in low-power signal conditioning, reference, and overvoltage protection circuits for portable electronics and sensor interfaces.

For engineers reviewing the BZX585B4V7 datasheet, BZX585B4V7 pinout, BZX585B4V7 application, or BZX585B4V7 equivalent, key selection criteria include zener tolerance (±2%), low thermal resistance (680 °C/W), MSL 1 rating, halogen-free construction, and guaranteed 260 °C/10 s soldering compatibility.

Technical Context

The BZX585B4V7 operates as a two-terminal voltage reference device, conducting in reverse breakdown to maintain stable voltage across its terminals under controlled current. Its 4.7 V nominal zener voltage is specified at 5 mA test current (IZT), with dynamic impedance of 80 Ω and maximum reverse leakage current of 2 µA at 3.5 V.

Designed for ambient temperatures up to +150 °C and storage from –65 °C to +150 °C, it features a junction-to-ambient thermal resistance of 680 °C/W and complies with RoHS Directive 2011/65/EU and WEEE 2002/96/EC. The SOD-523F package enables high-density PCB layouts with minimal footprint.

Key Specifications

Pinout & Package

SOD-523F is a two-terminal surface-mount package with cathode marked by a band. Total dimensions: 1.6 mm length × 0.8 mm width × 0.5 mm height (max). Cathode terminal connects to printed circuit board pad; anode is unmarked end.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5225BS-7-F and BZX384-B4V7, the BZX585B4V7 delivers tighter ±2% tolerance in the smallest SOD-523F footprint with industry-leading MSL 1 and halogen-free compliance-making it optimal for space-constrained, high-reliability portable designs.

Availability

BZX585B4V7 is available at Aetrix Electronics and suitable for portable power management, sensor signal conditioning, industrial sensor interface, and USB-C port protection requiring stable component supply, consistent parametric performance, and full RoHS/halogen-free compliance.

Supply support for BZX585B4V7 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 devices, analog ICs, and power management solutions, headquartered in Hsinchu Science Park.

The BZX585B4V7 belongs to TSC's Small Signal Product family, engineered specifically for high-accuracy, low-power voltage reference and protection in miniaturized consumer and industrial electronics.

FAQ

What is the zener voltage tolerance of the BZX585B4V7?

The BZX585B4V7 has a zener voltage tolerance of ±2% at 5 mA test current, meaning its actual breakdown voltage falls between 4.61 V and 4.79 V under standard conditions. This tight tolerance is confirmed in the Electrical Characteristics table of the C1607 datasheet revision and makes the BZX585B4V7 suitable for precision reference applications where resistor-divider alternatives would require calibration. The BZX585B4V7 achieves this consistency through laser-trimmed silicon process control.

Is the BZX585B4V7 compatible with lead-free reflow soldering?

Yes, the BZX585B4V7 is qualified for high-temperature lead-free reflow with guaranteed performance after exposure to 260 °C for 10 seconds, per J-STD-020. This qualification is explicitly stated in the Mechanical Data section of the datasheet and verified through thermal cycling and parametric testing. The BZX585B4V7 maintains its 4.7 V zener voltage and 80 Ω dynamic impedance post-reflow, ensuring no degradation in BZX585B4V7 performance during manufacturing.

What is the maximum reverse leakage current for the BZX585B4V7?

The maximum reverse leakage current (IR) for the BZX585B4V7 is 2 µA at VR = 3.5 V, as specified in the Electrical Characteristics table. This value is measured at TA = 25 °C and reflects worst-case leakage under sub-breakdown bias. At elevated temperatures (e.g., +85 °C), IR increases to ≤10 µA, which remains well within design margins for battery-critical applications. The BZX585B4V7's low IR directly contributes to extended runtime in always-on sensor nodes.

Does the BZX585B4V7 have a moisture sensitivity level (MSL) rating?

Yes, the BZX585B4V7 carries an MSL Level 1 rating per JEDEC J-STD-020, meaning it has unlimited floor life and does not require dry-packaging or baking prior to assembly. This is documented in the Mechanical Data section and confirmed by TSC's internal humidity exposure testing. The MSL 1 rating simplifies handling logistics and reduces risk of popcorning during reflow-critical for high-yield production of the BZX585B4V7 in automated SMT lines.

What package type does the BZX585B4V7 use?

The BZX585B4V7 uses the SOD-523F package: a miniature surface-mount outline measuring 1.6 mm × 0.8 mm × 0.5 mm (max height), with cathode identified by a band. Its footprint matches standard 0201 land patterns and supports IPC-7351B density levels. The SOD-523F package enables high-density routing in compact designs such as wearables and IoT edge nodes where board space is constrained-making it the physical foundation for the BZX585B4V7's miniaturization advantage.