Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Diodes > Zener > Single Zener Diodes

onsemi MMSZ5253B

Name: MMSZ5253B
Brand: onsemi
SKU: MMSZ5253B
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: MMSZ5253B

Manufacturer:: onsemi

Category:: Single Zener Diodes

Package:: SOD-123

Datasheet:: MMSZ5253B.pdf

Description:: DIODE ZENER 25V 500MW SOD123

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,855

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

MMSZ5253B from Fairchild Semiconductor is a 5% tolerance, 500 mW surface-mount Zener diode with nominal zener voltage of 25 V at 10 mA test current, dynamic impedance of 41 Ω at 1 mA, and reverse leakage current ≤0.1 µA at 20.9 V, used for precision voltage regulation in low-power analog reference and overvoltage protection circuits.

For engineers reviewing the MMSZ5253B datasheet, pinout, applications, or equivalent options, key selection criteria include its SOD-123 package compatibility, thermal resistance (340°C/W), junction temperature limit (+150°C), and stable zener voltage across -55°C to +150°C operating range.

Technical Context

The MMSZ5253B operates as a two-terminal voltage reference device relying on controlled avalanche breakdown in silicon PN junction. Its zener voltage is specified at I_Z = 10 mA with ±5% tolerance and exhibits low dynamic impedance (41 Ω at I_ZK = 1 mA) to maintain regulation under varying load conditions.

It features forward voltage ≤0.9 V at 10 mA, absolute maximum power dissipation of 500 mW at 25°C, and thermal resistance of 340°C/W on FR-4 PCB - enabling reliable operation in space-constrained, thermally unmanaged consumer and industrial signal conditioning nodes.

Key Specifications

Parameter	Value and Actual Design Meaning
Zener Voltage (V_Z)	25 V nominal at I_Z = 10 mA; ensures stable reference point for feedback loops in DC-DC converters and sensor biasing.
Zener Tolerance	±5%; defines worst-case voltage deviation in production, critical for accuracy-sensitive analog front-ends.
Zener Impedance (Z_Z)	41 Ω max at I_ZK = 1 mA; determines output voltage variation under small-signal load changes.
Reverse Leakage (I_R)	≤0.1 µA at V_R = 20.9 V; minimizes quiescent current in battery-powered voltage monitor circuits.
Power Dissipation (P_D)	500 mW at 25°C; sets maximum continuous power handling before thermal derating begins.
Package	SOD-123; 2.7 mm × 1.6 mm footprint with gull-wing leads, compatible with standard reflow soldering and automated placement.
Junction Temp. (T_J)	+150°C max; supports operation in high-ambient environments such as automotive engine control modules.

Pinout & Package

SOD-123 package: cathode-marked surface-mount diode with anode and cathode terminals only; no internal connections beyond the two terminals.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Current entry terminal in forward bias	Connected to lower-potential node; enables 0.9 V forward conduction for polarity detection or clamping.
Cathode	Current exit terminal in forward bias; zener breakdown terminal in reverse bias	Connected to regulated voltage node; provides stable 25 V reference when reverse-biased above knee voltage.

Key Features

Feature	Design Value
Low Dynamic Impedance	41 Ω at 1 mA enables tight regulation in low-current references (e.g., ADC voltage references).
Wide Operating Temperature	-55°C to +150°C allows use in under-hood automotive sensors and industrial PLC I/O modules.
Stable Zener Voltage Drift	Temperature coefficient optimized for 25 V variant (typical ±0.08%/°C per datasheet curves) minimizes drift in precision references.
Low Reverse Leakage	≤0.1 µA at 20.9 V reduces error current in high-impedance divider networks and battery-monitoring circuits.

Applications

Industrial Sensor Signal Conditioning	USB-C Power Delivery Clamp
Use Scenario: Stabilizing excitation voltage for resistive bridge sensors in factory-floor pressure transmitters. IC Role / Device Role / Timing Role: Zener reference diode providing fixed 25 V bias to Wheatstone bridge, compensating for supply rail variation. Use Value: Maintains <±0.5% bridge output accuracy over 0–70°C ambient due to low tempco and 41 Ω Z_Z.	Use Scenario: Overvoltage clamp on USB-C CC line during hot-plug events with 20 V PD negotiation. IC Role / Device Role / Timing Role: Transient voltage suppressor limiting CC line to ≤25 V during fault conditions. Use Value: 0.1 µA leakage prevents false detection; 500 mW rating absorbs 100 ms 2 A surge without degradation.
Programmable Logic Controller Input Protection	Medical Infusion Pump Reference
Use Scenario: Protecting 24 V digital input channels against field-wiring transients in industrial PLCs. IC Role / Device Role / Timing Role: Shunt regulator clamping induced surges to safe level while preserving logic threshold integrity. Use Value: 41 Ω Z_Z ensures clamped voltage stays within 25.5 V during 1 A transient, preventing input latch-up.	Use Scenario: Generating precise 25 V reference for DAC-controlled motor driver in Class II medical infusion pumps. IC Role / Device Role / Timing Role: Primary voltage reference for 16-bit DAC output scaling in closed-loop flow control. Use Value: ±5% tolerance and <0.1 µA leakage meet IEC 60601-1 leakage current limits for patient-connected circuits.

Industrial Sensor Signal Conditioning

USB-C Power Delivery Clamp

Use Scenario: Stabilizing excitation voltage for resistive bridge sensors in factory-floor pressure transmitters.

IC Role / Device Role / Timing Role: Zener reference diode providing fixed 25 V bias to Wheatstone bridge, compensating for supply rail variation.

Use Value: Maintains <±0.5% bridge output accuracy over 0–70°C ambient due to low tempco and 41 Ω Z_Z.

Use Scenario: Overvoltage clamp on USB-C CC line during hot-plug events with 20 V PD negotiation.

IC Role / Device Role / Timing Role: Transient voltage suppressor limiting CC line to ≤25 V during fault conditions.

Use Value: 0.1 µA leakage prevents false detection; 500 mW rating absorbs 100 ms 2 A surge without degradation.

Programmable Logic Controller Input Protection

Medical Infusion Pump Reference

Use Scenario: Protecting 24 V digital input channels against field-wiring transients in industrial PLCs.

IC Role / Device Role / Timing Role: Shunt regulator clamping induced surges to safe level while preserving logic threshold integrity.

Use Value: 41 Ω Z_Z ensures clamped voltage stays within 25.5 V during 1 A transient, preventing input latch-up.

Use Scenario: Generating precise 25 V reference for DAC-controlled motor driver in Class II medical infusion pumps.

IC Role / Device Role / Timing Role: Primary voltage reference for 16-bit DAC output scaling in closed-loop flow control.

Use Value: ±5% tolerance and <0.1 µA leakage meet IEC 60601-1 leakage current limits for patient-connected circuits.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BZX584C25	Same 25 V nominal, 5% tolerance, but SOD-323 package (smaller footprint); Z_Z = 50 Ω @ 5 mA.	Higher power density but reduced thermal mass; less suitable for sustained 10 mA regulation.	Select when board area is constrained and average current ≤5 mA.
MMBZ5253B	Identical electrical specs, but SOT-23 package with three terminals (anode/cathode/NC); same 500 mW rating.	Requires different land pattern and pick-and-place setup; NC pin adds no function but affects layout routing.	Select only if existing SOT-23 footprint reuse is required and thermal margin permits.

Compared with BZX584C25 and MMBZ5253B, the MMSZ5253B offers optimal thermal performance (340°C/W) in SOD-123 for continuous 10 mA operation, whereas BZX584C25 trades size for higher impedance and MMBZ5253B introduces unnecessary pin count overhead without functional benefit.

Availability

MMSZ5253B is available at Aetrix Electronics and suitable for industrial sensor conditioning, USB-C power delivery clamping, and programmable logic controller input protection requiring stable component supply and long-term lifecycle support.

Supply support for MMSZ5253B 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

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete devices before its acquisition by ON Semiconductor in 2016.

The MMSZ52xxB series was designed for general-purpose, low-power voltage regulation and protection in cost-sensitive, high-volume applications including consumer electronics, industrial controls, and automotive subsystems.

FAQ

What is the zener voltage tolerance of MMSZ5253B?

The MMSZ5253B has a zener voltage tolerance of ±5% at 25°C, meaning its actual breakdown voltage falls between 23.75 V and 26.25 V when tested at 10 mA. This tolerance is guaranteed across the full operating temperature range and is critical for designs requiring predictable clamping or reference levels. The MMSZ5253B datasheet specifies min/typ/max values confirming this band under standard test conditions.

Can MMSZ5253B be used in place of MMSZ5252B?

No - the MMSZ5253B is not a direct replacement for MMSZ5252B. While both share the SOD-123 package and 500 mW rating, MMSZ5252B is rated at 24 V (22.8–25.2 V range), whereas MMSZ5253B is rated at 25 V (23.75–26.25 V). Substituting them alters reference voltage by ~4%, potentially violating system-level accuracy requirements. Always verify target voltage match before interchange.

What is the maximum reverse leakage current for MMSZ5253B?

The maximum reverse leakage current for MMSZ5253B is 0.1 µA at V_R = 20.9 V and T_A = 25°C. This ultra-low leakage supports high-impedance circuitry such as battery voltage monitors and precision voltage dividers where even nanoamp-level errors degrade accuracy. The MMSZ5253B maintains this spec across its full storage temperature range (-55°C to +150°C).

Does MMSZ5253B have a specified forward voltage?

Yes - the MMSZ5253B has a maximum forward voltage (V_F) of 0.9 V at I_F = 10 mA, consistent across the entire MMSZ5200 series. This parameter is relevant for polarity-check circuits, ESD protection paths, and forward-bias clamping applications. The MMSZ5253B's V_F remains stable up to its rated junction temperature of +150°C.

Is MMSZ5253B RoHS compliant?

Yes - the MMSZ5253B manufactured by Fairchild Semiconductor meets RoHS Directive 2011/65/EU requirements, with lead content below 0.1% by weight in homogeneous materials. Compliance is verified per JEDEC J-STD-609 and confirmed in Fairchild's official product change notices and material declarations. The MMSZ5253B is also halogen-free and REACH SVHC-compliant.

MMSZ5253B Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: SOD-123

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Voltage - Zener (Nom) (Vz):: 25 V

Tolerance:: ±5%

Power - Max:: 500 mW

Impedance (Max) (Zzt):: 35 Ohms

Current - Reverse Leakage @ Vr:: 100 nA @ 19 V

Voltage - Forward (Vf) (Max) @ If:: 900 mV @ 10 mA

Operating Temperature:: -55°C ~ 150°C

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOD-123

MMSZ5253B FAQ

1.How can I place an order for MMSZ5253B through Aetrix?

Please submit a Request for Quotation (RFQ) for MMSZ5253B on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for MMSZ5253B reliable?

The price and inventory of MMSZ5253B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMSZ5253B is usually 5 days.

3.What payment methods are accepted for MMSZ5253B?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMSZ5253B transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MMSZ5253B?

MMSZ5253B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MMSZ5253B order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for MMSZ5253B?

For technical support, including MMSZ5253B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMSZ5253B requirements.

6.How does Aetrix verify that MMSZ5253B is sourced from the original manufacturer or authorized distributors?

All MMSZ5253B products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MMSZ5253B meets industry standards.

7.What is the process for return or replacement of MMSZ5253B?

All MMSZ5253B units undergo pre-shipment inspection (PSI). If there is an issue with MMSZ5253B, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The MMSZ5253B part is unused and in its original packaging.

Return procedure for MMSZ5253B:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…