onsemi MMBZ5230BLT3G

Overview

MMBZ5230BLT3G from onsemi is a 4.7 V ±5% Zener diode in SOT-23 package, rated for 225 mW power dissipation on FR-5 board at 25°C, with 19 Ω dynamic impedance at 20 mA test current and 5 μA reverse leakage at 2 V. It serves as a precision voltage reference or overvoltage clamp in low-power portable electronics.

For engineers reviewing the MMBZ5230BLT3G datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, thermal derating behavior, ESD robustness (Class 3, >16 kV HBM), and validated alternative parts for voltage regulation design.

Technical Context

This Zener diode operates in reverse breakdown to maintain stable voltage across its cathode-anode terminals under varying load currents. Its nominal 4.7 V Zener voltage is specified at 20 mA test current (IZT), with tight tolerance (±5%) and low dynamic impedance (19 Ω) ensuring minimal voltage deviation during transient current changes.

Thermal performance is defined by 556 °C/W junction-to-ambient resistance on FR-5 board, requiring derating of 1.8 mW/°C above 25°C ambient. The device supports operation from −65°C to +150°C junction temperature and features Class 3 ESD protection (>16 kV HBM), making it suitable for handheld and high-density PCB environments.

Key Specifications

Pinout & Package

SOT-23 (TO-236) surface-mount package, 2.90 mm × 1.30 mm × 1.00 mm body size, Pb-free and RoHS compliant. Cathode identified by polarity band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMBZ5230BLT3G, BZX84-C4V7LT1G trades tighter impedance for higher surge capability, while MMBZ5230BS retains identical regulation performance but requires PCB redesign due to SOD-123 footprint - neither is pin-compatible, but both serve overlapping voltage-reference roles in cost- or thermal-sensitive designs.

Availability

MMBZ5230BLT3G is available at Aetrix Electronics and suitable for smartphone power rail clamping, USB port overvoltage protection, wearable sensor bias referencing, and IoT node battery monitoring requiring stable component supply and consistent Zener voltage performance.

Supply support for MMBZ5230BLT3G 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The MMBZ52xxBLT3G series belongs to onsemi's precision Zener voltage regulator product line, engineered for space-constrained, low-power voltage reference and overvoltage protection in portable and high-density electronics.

FAQ

What is the Zener voltage tolerance of MMBZ5230BLT3G?

The MMBZ5230BLT3G has a nominal Zener voltage of 4.7 V with a tolerance of ±5%, meaning the actual measured voltage at 20 mA test current falls between 4.46 V and 4.94 V. This tolerance is guaranteed across the full operating temperature range and is verified per onsemi's production testing protocol - not a statistical estimate. The MMBZ5230BLT3G maintains this specification without requiring external trimming or calibration.

Does MMBZ5230BLT3G have a connected pin 2?

No, pin 2 of the MMBZ5230BLT3G is internally not connected (NC). The device uses a three-terminal SOT-23 package with only pins 1 (anode) and 3 (cathode) electrically active. Pin 2 must remain unconnected on the PCB - no trace, via, or solder mask opening is required. This NC configuration is confirmed in the mechanical outline (Style 8) and electrical characteristics table of the official onsemi datasheet for MMBZ5230BLT3G.

What is the maximum reverse leakage current for MMBZ5230BLT3G?

The maximum reverse leakage current for MMBZ5230BLT3G is 5 μA at a reverse voltage (V_R) of 2 V and ambient temperature of 25°C. This value is specified in the Electrical Characteristics table and reflects worst-case leakage under standard test conditions. At lower voltages (e.g., 1 V), leakage drops further - typically below 0.1 μA - making the MMBZ5230BLT3G suitable for ultra-low-power battery-monitoring applications where standby current must be minimized.

Can MMBZ5230BLT3G be used in automotive applications?

The standard MMBZ5230BLT3G is not AEC-Q101 qualified; however, the SZMMBZ5230BLT3G variant - with identical electrical specs and SOT-23 packaging - is fully AEC-Q101 qualified and PPAP capable. For automotive-grade deployment, designers must specify the SZ-prefix part. The MMBZ5230BLT3G itself is rated for −65°C to +150°C junction temperature and meets Class 3 HBM ESD requirements, but lacks the process controls and traceability required for automotive qualification.

How does thermal derating affect MMBZ5230BLT3G's power handling?

MMBZ5230BLT3G's 225 mW power rating applies only at 25°C ambient on FR-5 board; above that, it derates linearly at 1.8 mW/°C. At 85°C ambient, usable power drops to 117 mW (225 − (85−25) × 1.8). This derating is based on 556 °C/W junction-to-ambient thermal resistance and must be applied in thermal design calculations. Exceeding derated limits risks parametric shift or permanent degradation - the MMBZ5230BLT3G does not include internal thermal shutdown.