onsemi MMSZ5241BT1

Overview

MMSZ5241BT1 from ON Semiconductor is a 5% tolerance, 11 V nominal Zener voltage regulator diode in SOD−123 surface-mount package, rated for 500 mW power dissipation on FR−5 board at 75°C, with 22 Ω maximum Zener impedance at 20 mA test current and 2 µA reverse leakage at 8.4 V, used for precision voltage reference and overvoltage protection in low-power analog circuits.

For engineers reviewing the MMSZ5241BT1 datasheet, pinout, applications, or equivalent options, this device serves as a compact, Pb−free, AEC−Q101–capable Zener regulator optimized for thermal equilibrium operation, stable DC biasing, and ESD-robust (Class 3, >16 kV HBM) signal conditioning in space-constrained industrial and automotive subsystems.

Technical Context

This Zener diode operates in reverse breakdown mode with junction temperature range from −55°C to +150°C and thermal resistance of 340°C/W (junction-to-ambient) and 150°C/W (junction-to-lead). Its Zener voltage is specified under thermal equilibrium conditions at TL = 30°C ±1°C, ensuring stable regulation across ambient variations.

The device exhibits a typical temperature coefficient of +5.5 mV/°C near 11 V, low capacitance (<10 pF at 50% VZ), and forward voltage ≤0.95 V at 10 mA - enabling reliable clamping, reference generation, and noise-sensitive biasing without thermal runaway or parasitic coupling.

Key Specifications

Pinout & Package

SOD−123 plastic surface-mount package with cathode indicated by polarity band; void-free thermosetting case, UL 94 V−0 flammability rating, and 260°C/10 sec maximum soldering temperature.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ5241BT1, BZX584C11 offers higher voltage accuracy but sacrifices 50% power capability and requires layout revision for SOD-323, while MMSZ5241BS delivers identical regulation performance with alternate surface finish - making MMSZ5241BT1 the optimal balance of precision, robustness, and manufacturability for new designs.

Availability

MMSZ5241BT1 is available at Aetrix Electronics and suitable for industrial sensor interfaces, automotive body electronics, and portable medical devices requiring stable component supply, long-term lifecycle support, and AEC−Q101–qualified passive components.

Supply support for MMSZ5241BT1 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, and sensor solutions for automotive, industrial, and cloud infrastructure markets.

The MMSZ52xxxT1G series was designed to deliver high-reliability, surface-mount Zener regulation for space-constrained, thermally demanding applications - emphasizing AEC−Q101 qualification, Pb−free compliance, and thermal equilibrium voltage stability.

FAQ

What is the Zener voltage tolerance for MMSZ5241BT1?

The MMSZ5241BT1 has a ±5% tolerance on its nominal 11 V Zener voltage, resulting in a guaranteed range of 10.45 V to 11.55 V when measured at I_ZT = 20 mA and thermal equilibrium (TL = 30°C ±1°C). This tolerance is confirmed in the "5% TOLERANCE FG ELECTRICAL CHARACTERISTICS" table on page 3 of the ON Semiconductor datasheet. The "B" suffix explicitly denotes the 5% grade, distinguishing it from "C"-suffix 2% variants like MMSZ5241CT1G.

Does MMSZ5241BT1 meet automotive qualification standards?

Yes, MMSZ5241BT1 is AEC−Q101 qualified and PPAP capable, as stated in the "Features" section of the datasheet. It carries the "SZ" prefix option (e.g., SZMMSZ5241BT1G) for automotive-specific change control and site requirements. The device's ESD rating (>16 kV HBM), extended junction temperature range (−55°C to +150°C), and thermal equilibrium Zener specification make it suitable for under-hood and cabin electronics where reliability under thermal stress is critical.

What is the maximum reverse leakage current for MMSZ5241BT1?

The maximum reverse leakage current for MMSZ5241BT1 is 2 µA at V_R = 8.4 V, as specified in the Electrical Characteristics table on page 3. This value is measured at TA = 25°C and reflects the device's ability to maintain low standby power in high-impedance bias networks. Leakage remains below 0.1 µA at VR ≤ 5 V, supporting precision reference applications where quiescent current must be minimized.

Can MMSZ5241BT1 be used in place of MMSZ5241BT1G?

MMSZ5241BT1 and MMSZ5241BT1G are functionally identical - the "G" suffix denotes Pb−free packaging, which is standard for all current production. ON Semiconductor's ordering information confirms both part numbers share the same SOD−123 package, electrical specs, and thermal ratings. No design or layout changes are needed when transitioning between them; MMSZ5241BT1G is the modern, RoHS-compliant version of MMSZ5241BT1.

What is the thermal resistance of MMSZ5241BT1?

MMSZ5241BT1 has a thermal resistance of 340°C/W (junction-to-ambient, R_JA) and 150°C/W (junction-to-lead, R_JL), measured per infrared scan method on FR−5 board. These values define the temperature rise per watt dissipated and directly impact safe operating area - for example, at 500 mW dissipation, junction temperature rises ~170°C above ambient, necessitating board-level thermal relief (e.g., copper pour) to stay within the −55°C to +150°C TJ limit.