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

onsemi MMSZ43T1

Name: MMSZ43T1
Brand: onsemi
SKU: MMSZ43T1
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: MMSZ43T1

Manufacturer:: onsemi

Category:: Single Zener Diodes

Package:: SOD-123

Datasheet:: MMSZ43T1.pdf

Description:: DIODE ZENER 43V 500MW SOD123

Quantity:: RFQ Add To RFQ list

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Inventory:3,536

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Product details

Overview

MMSZ43T1G from onsemi is a 43 V ±5% Zener voltage regulator diode in SOD−123 surface-mount package, rated for 500 mW power dissipation at 75°C, with 150 Ω maximum dynamic impedance at 2 mA test current and 0.05 µA reverse leakage at 30.1 V. It serves as a precision voltage reference or overvoltage clamp in low-power analog and power management circuits.

For engineers reviewing the MMSZ43T1G datasheet, pinout, applications, or equivalent options, this device is selected for stable 43 V regulation in space-constrained, high-density PCBs where AEC−Q101 qualification, ESD robustness (>16 kV HBM), and thermal reliability across −55°C to +150°C are required.

Technical Context

This Zener diode operates in reverse breakdown mode with nominal V_Z = 43 V at I_ZT = 2 mA, exhibiting a temperature coefficient of approximately +3.3 mV/°C (typical for 43 V devices per Figure 1). Its dynamic impedance (Z_ZT) is specified at 150 Ω max under AC conditions (f = 1 kHz, I_Z(AC) = 0.1 × I_Z(DC)).

The device uses a thermosetting plastic SOD−123 case with UL 94 V−0 flammability rating, cathode polarity marked by band, and Pb−free construction. Junction-to-ambient thermal resistance is 340°C/W on FR−5 board, supporting operation up to 150°C junction temperature with appropriate derating.

Key Specifications

Parameter	Value and Actual Design Meaning
Zener Voltage (V_Z)	40.85–45.15 V at I_ZT = 2 mA - defines precise clamping/reference level with ±5% tolerance
Power Dissipation (P_D)	500 mW @ T_L = 75°C - sets maximum continuous DC power handling on standard PCB
Zener Impedance (Z_ZT)	≤150 Ω @ I_ZT = 2 mA - determines voltage regulation stability under load transients
Reverse Leakage (I_R)	≤0.05 µA @ V_R = 30.1 V - ensures minimal standby current in high-impedance bias networks
Thermal Resistance (R_JA)	340°C/W - quantifies self-heating impact; requires layout attention for >100 mW operation
ESD Rating	Class 3 (>16 kV HBM) - enables safe handling and assembly without special ESD controls
Junction Temp Range	−55°C to +150°C - supports automotive under-hood and industrial ambient environments

Pinout & Package

SOD−123 surface-mount package: 2-terminal, 1.60 mm × 2.69 mm × 1.16 mm body, void-free thermosetting plastic case, cathode indicated by band. Maximum soldering temperature: 260°C for 10 seconds.

Pin/Terminal	Circuit Role	Design Meaning
1 (Banded End)	Cathode	Connected to regulated output or voltage reference node; reverse-biased during Zener operation
2 (Non-banded End)	Anode	Typically tied to ground or lower-potential rail; completes reverse-bias path for regulation

Key Features

Feature	Design Value
500 mW Power Rating on FR−5 Board	Enables use in compact power rails without external heat sinking at moderate ambient temperatures
AEC−Q101 Qualified	Validated for automotive electronics applications including infotainment and body control modules
ESD Robustness >16 kV (HBM)	Reduces risk of field failure due to handling or system-level ESD events in end equipment
Pb−Free Construction	Complies with RoHS Directive 2011/65/EU and JEDEC J-STD-020 reflow profile requirements
Small SOD−123 Footprint	Supports high-density routing in portable and IoT devices where board area is constrained

Applications

Automotive Sensor Biasing	Industrial Analog Signal Clamping
Use Scenario: Providing stable 43 V bias to Hall-effect or pressure sensors in engine control units. IC Role / Device Role / Timing Role: Precision voltage reference for sensor excitation circuitry. Use Value: Maintains sensor accuracy across −40°C to +125°C ambient with <±0.5% drift over temperature.	Use Scenario: Limiting input voltage to ADC front-end stages in programmable logic controllers. IC Role / Device Role / Timing Role: Overvoltage protection clamp preventing ADC saturation or damage. Use Value: Limits transient spikes to ≤45.15 V while drawing <0.05 µA at normal operating voltage.
Portable Medical Device Reference	Telecom Power Supervision
Use Scenario: Generating fixed reference for battery voltage monitoring in handheld diagnostic tools. IC Role / Device Role / Timing Role: Low-current Zener shunt reference in ultra-low-power sleep mode. Use Value: Draws only 0.05 µA leakage at 30.1 V, extending battery life in multi-year deployments.	Use Scenario: Monitoring 48 V telecom supply rails for undervoltage/overvoltage fault detection. IC Role / Device Role / Timing Role: Threshold detector in discrete supervisor circuitry. Use Value: Provides sharp 43 V turn-on knee with 150 Ω dynamic impedance for reliable trip-point repeatability.

Automotive Sensor Biasing

Industrial Analog Signal Clamping

Use Scenario: Providing stable 43 V bias to Hall-effect or pressure sensors in engine control units.

IC Role / Device Role / Timing Role: Precision voltage reference for sensor excitation circuitry.

Use Value: Maintains sensor accuracy across −40°C to +125°C ambient with <±0.5% drift over temperature.

Use Scenario: Limiting input voltage to ADC front-end stages in programmable logic controllers.

IC Role / Device Role / Timing Role: Overvoltage protection clamp preventing ADC saturation or damage.

Use Value: Limits transient spikes to ≤45.15 V while drawing <0.05 µA at normal operating voltage.

Portable Medical Device Reference

Telecom Power Supervision

Use Scenario: Generating fixed reference for battery voltage monitoring in handheld diagnostic tools.

IC Role / Device Role / Timing Role: Low-current Zener shunt reference in ultra-low-power sleep mode.

Use Value: Draws only 0.05 µA leakage at 30.1 V, extending battery life in multi-year deployments.

Use Scenario: Monitoring 48 V telecom supply rails for undervoltage/overvoltage fault detection.

IC Role / Device Role / Timing Role: Threshold detector in discrete supervisor circuitry.

Use Value: Provides sharp 43 V turn-on knee with 150 Ω dynamic impedance for reliable trip-point repeatability.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BZX84-C43	Same 43 V nominal Zener, but SOT−23 package (higher R_JA = 375°C/W); 350 mW rating	Lower power handling and larger footprint; not AEC−Q101 qualified	Select when cost sensitivity outweighs automotive qualification and thermal performance needs
1N4747A	Through-hole DO−41 package; 1 W rating; ±5% tolerance; higher Z_ZT (200 Ω typical)	Requires PCB through-holes; unsuitable for automated SMT lines or high-density layouts	Select only for legacy through-hole designs or prototyping where manual assembly is acceptable

Compared with BZX84-C43 and 1N4747A, the MMSZ43T1G delivers superior thermal performance in SMT production, AEC−Q101 compliance for automotive use, and tighter dynamic impedance control-making it optimal for modern high-reliability, space-constrained applications.

Availability

MMSZ43T1G is available at Aetrix Electronics and suitable for automotive sensor biasing, industrial analog signal clamping, and portable medical device reference requiring stable component supply, full traceability, and long-term lifecycle support.

Supply support for MMSZ43T1G 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 (Semiconductor Components Industries, LLC) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The MMSZxxxT1G series was designed specifically for surface-mount Zener regulation in high-volume, high-reliability applications-emphasizing AEC−Q101 qualification, ESD robustness, and tight parametric control across wide temperature ranges.

FAQ

What is the Zener voltage tolerance for MMSZ43T1G?

The MMSZ43T1G has a nominal Zener voltage of 43 V with a standard tolerance of ±5%, resulting in a guaranteed range of 40.85 V to 45.15 V when tested at I_ZT = 2 mA and T_A = 25°C. This tolerance remains valid across the full operating temperature range of −55°C to +150°C, as confirmed in the Electrical Characteristics table on page 3 of the official onsemi datasheet.

Is MMSZ43T1G suitable for automotive applications?

Yes, the MMSZ43T1G is AEC−Q101 qualified and PPAP capable, making it suitable for automotive applications such as sensor biasing, power rail supervision, and ECU voltage reference circuits. Its construction meets automotive reliability standards, including high-temperature operation up to +150°C junction temperature and robust ESD immunity (>16 kV HBM).

What is the maximum reverse leakage current for MMSZ43T1G?

The maximum reverse leakage current for MMSZ43T1G is 0.05 µA at V_R = 30.1 V and T_A = 25°C, as specified in the Electrical Characteristics table. This ultra-low leakage supports high-impedance bias networks and extends battery life in always-on portable systems where MMSZ43T1G serves as a reference or clamp.

Does MMSZ43T1G have Pb−free packaging?

Yes, the "G" suffix in MMSZ43T1G denotes a Pb−free package compliant with RoHS Directive 2011/65/EU. The device uses lead-free terminations and conforms to JEDEC J-STD-020 moisture sensitivity and reflow profile requirements, enabling compatibility with standard lead-free SMT assembly processes.

What is the thermal resistance of MMSZ43T1G on FR−5 board?

The thermal resistance, junction-to-ambient (R_JA), for MMSZ43T1G is 340°C/W when mounted on FR−5 board, as stated in the Maximum Ratings table. This value assumes standard 3.5″ × 1.5″ board size and guides thermal design for continuous operation-e.g., at 250 mW dissipation, junction temperature rise above ambient is ~85°C.

MMSZ43T1 Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: SOD-123

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Voltage - Zener (Nom) (Vz):: 43 V

Tolerance:: ±5%

Power - Max:: 500 mW

Impedance (Max) (Zzt):: 150 Ohms

Current - Reverse Leakage @ Vr:: 50 nA @ 30.1 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

MMSZ43T1 FAQ

1.How can I place an order for MMSZ43T1 through Aetrix?

Please submit a Request for Quotation (RFQ) for MMSZ43T1 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 MMSZ43T1 reliable?

The price and inventory of MMSZ43T1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMSZ43T1 is usually 5 days.

3.What payment methods are accepted for MMSZ43T1?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMSZ43T1 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MMSZ43T1?

MMSZ43T1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MMSZ43T1 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 MMSZ43T1?

For technical support, including MMSZ43T1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMSZ43T1 requirements.

6.How does Aetrix verify that MMSZ43T1 is sourced from the original manufacturer or authorized distributors?

All MMSZ43T1 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 MMSZ43T1 meets industry standards.

7.What is the process for return or replacement of MMSZ43T1?

All MMSZ43T1 units undergo pre-shipment inspection (PSI). If there is an issue with MMSZ43T1, 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 MMSZ43T1 part is unused and in its original packaging.

Return procedure for MMSZ43T1:

1.Submit a request within 90 days.

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

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