Diodes Incorporated MMBZ5248BT-7-F

Overview

MMBZ5248BT-7-F from Diodes Incorporated is a 18 V, 150 mW surface-mount Zener diode in SOT-523 package, with nominal Zener voltage 18.0 V (min 17.1 V, max 18.9 V), test current 7.0 mA, and maximum Zener impedance 21 Ω at 1 kHz; used for precision voltage regulation and overvoltage protection in space-constrained power management circuits.

For engineers reviewing the MMBZ5248BT-7-F datasheet, MMBZ5248BT-7-F pinout, MMBZ5248BT-7-F application, or MMBZ5248BT-7-F equivalent, key selection criteria include Zener voltage tolerance, dynamic impedance at specified test current, thermal resistance (833 °C/W), reverse leakage (<0.1 μA at 14 V), and SOT-523 footprint compatibility with high-density PCB layouts.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable reference voltage under varying load and temperature conditions. Its planar die construction ensures consistent breakdown characteristics and low leakage, while the ultra-small SOT-523 package supports automated placement in compact consumer and industrial electronics.

It delivers regulated output across ambient temperatures from –65 °C to +150 °C with power derating above 25 °C, and exhibits typical total capacitance of ~15 pF at 18 V - suitable for low-frequency regulation rather than high-speed signal clamping.

Key Specifications

Pinout & Package

Package: SOT-523 - ultra-compact 3-pin surface-mount plastic case (1.6 mm × 0.8 mm × 0.5 mm), moisture sensitivity level 1, lead-free matte tin plating, polarity indicated by cathode band.

Key Features

Applications

Availability

MMBZ5248BT-7-F is available at Aetrix Electronics and suitable for microcontroller I/O protection, low-power sensor reference, and portable power supply regulation requiring stable component supply and RoHS-compliant sourcing.

Supply support for MMBZ5248BT-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, specializing in high-reliability, energy-efficient components for industrial, computing, and consumer markets.

The MMBZ52xxBT series belongs to Diodes' general-purpose Zener diode product line, designed specifically for compact, cost-sensitive voltage regulation and protection applications in surface-mount assemblies.

FAQ

What is the maximum reverse voltage before breakdown for MMBZ5248BT-7-F?

The device exhibits sharp Zener breakdown at nominal 18.0 V, with guaranteed range 17.1–18.9 V at 7.0 mA test current. Below 14 V, reverse leakage remains below 0.1 μA - confirming no significant conduction until near rated Zener voltage.

Can MMBZ5248BT-7-F replace MMBZ5245BT in a 15 V circuit?

No - MMBZ5245BT is rated 15 V (±5%), while MMBZ5248BT-7-F is 18 V (±5%). Substituting would raise regulated voltage by 3 V, potentially exceeding downstream component ratings and altering feedback loop setpoints.

Is thermal derating required for continuous operation at 70 °C ambient?

Yes - with R_θJA = 833 °C/W, junction temperature rise at full 150 mW is ~125 °C. At 70 °C ambient, max allowable power drops to ~90 mW (derated by ~40%) to stay within 150 °C T_J limit.

Does this Zener diode have a specified capacitance value?

Yes - typical total capacitance is 15 pF at 18 V (per Fig. 4 in DS30267 Rev. 11-2), measured at 1 MHz. This low value supports use in low-frequency regulation without affecting signal integrity in analog interfaces.