My Inquiry
My Account
onsemi MMSZ5231B
- Part No.:
- MMSZ5231B
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- SOD-123
- Datasheet:
-
MMSZ5231B.pdf
- Description:
- DIODE ZENER 5.1V 500MW SOD123
- Quantity:
- Payment:
- Shipping:
Inventory:2,177
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MMSZ5231B from ON Semiconductor (formerly Fairchild) is a 5.1 V, 500 mW surface-mount Zener diode in SOD-123 package, with 5% tolerance, 17 Ω dynamic impedance at 20 mA, and 2 µA reverse leakage at 3.8 V, used for precision voltage regulation and reference in low-power analog circuits.
For engineers reviewing the MMSZ5231B datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage accuracy, thermal resistance (340°C/W), forward voltage (≤0.9 V @ 10 mA), and compatibility with FR-4 PCB layouts requiring minimal land pads.
Technical Context
The MMSZ5231B operates as a two-terminal voltage reference device, clamping reverse-biased voltage at nominal 5.1 V with ±5% tolerance across temperature. Its Zener impedance of 17 Ω at 20 mA ensures stable regulation under moderate load transients.
Designed for operation up to +150°C junction temperature and rated for 500 mW power dissipation at 25°C, it relies on thermal conduction through the SOD-123 package's cathode/anode terminals, with storage range spanning −55°C to +150°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 4.845–4.935 V min–max at IZ = 20 mA; enables precise 5.1 V rail stabilization in sensor biasing and ADC reference circuits. |
| Zener Impedance (ZZ) | 17 Ω max at IZ = 20 mA; limits output voltage deviation during current step changes in feedback loops. |
| Reverse Leakage (IR) | 2.0 µA max at VR = 3.8 V; minimizes quiescent current draw in battery-powered voltage monitor designs. |
| Power Dissipation (PD) | 500 mW at TA = 25°C; defines maximum continuous DC power handling before thermal derating applies. |
| Forward Voltage (VF) | ≤0.9 V at IF = 10 mA; supports use as low-drop rectifier or ESD clamp in signal path protection. |
| Thermal Resistance (RθJA) | 340°C/W on FR-4 board; determines junction-to-ambient temperature rise per watt-critical for layout thermal pad sizing. |
Pinout & Package
SOD-123 plastic surface-mount package with cathode band marking; 2-terminal configuration requiring no external biasing or control signals.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal in forward bias; voltage reference return node in reverse bias | Connected to circuit ground or lowest potential node when used as shunt regulator. |
| Cathode | Current exit terminal in forward bias; regulated output node in reverse bias | Connected to supply rail or reference point requiring stabilized 5.1 V; marked by band on package body. |
Key Features
| Feature | Design Value |
|---|---|
| ±5% Zener voltage tolerance | Ensures predictable clamping within 0.255 V of nominal 5.1 V-sufficient for non-critical analog references and overvoltage protection. |
| Low forward voltage (≤0.9 V) | Permits dual-use as ESD protection diode in I/O lines without introducing significant signal path loss. |
| 340°C/W thermal resistance | Enables reliable operation on standard FR-4 PCBs with minimum recommended land pads-no thermal vias required for ≤100 mW average dissipation. |
| −55°C to +150°C operating range | Supports deployment in automotive cabin modules, industrial sensors, and outdoor metering where ambient extremes occur. |
Applications
| Temperature-Sensitive Sensor Biasing | Microcontroller Reset Voltage Reference |
|---|---|
Use Scenario: Providing stable bias current to thermistor or RTD front-end amplifiers in HVAC control units. IC Role / Device Role / Timing Role: Shunt voltage reference establishing fixed 5.1 V node for op-amp input common-mode level. Use Value: Maintains <±10 mV drift over −40°C to +85°C ambient due to matched Zener tempco and low IR variation. | Use Scenario: Generating clean reset threshold for 3.3 V microcontrollers in smart home hubs. IC Role / Device Role / Timing Role: Reverse-biased Zener feeding comparator input to trigger POR (power-on reset) at defined rail level. Use Value: Delivers repeatable 5.1 V trip point with <1 µA leakage-prevents false resets during slow-ramp power-up. |
| Low-Power Analog Signal Clamping | USB Data Line ESD Protection |
Use Scenario: Limiting op-amp output swing to prevent saturation in battery-operated medical pulse monitors. IC Role / Device Role / Timing Role: Bidirectional clamp using forward and reverse conduction paths. Use Value: Forward VF ≤0.9 V and reverse VZ = 5.1 V jointly constrain signal between −0.9 V and +5.1 V-preserving ADC full-scale range. | Use Scenario: Protecting USB 2.0 D+ and D− lines from IEC 61000-4-2 contact discharge events. IC Role / Device Role / Timing Role: Low-capacitance transient suppressor placed in parallel with data lines. Use Value: Sub-100 pF junction capacitance and 2 µA leakage avoid signal integrity degradation while clamping >8 kV ESD pulses. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX584C5V1 | Same 5.1 V nominal, 5% tolerance, but SOD-323 package (smaller footprint); RθJA = 450°C/W; IR = 2 µA @ 3.8 V | Higher thermal resistance limits power handling to ~350 mW; preferred for space-constrained portable designs. | Select BZX584C5V1 only if PCB area is constrained and thermal margin permits lower PD. |
| MM3Z5V1T1G | Same 5.1 V, 5% tolerance, SOD-323 package; tighter IR = 0.1 µA @ 3.8 V; ZZ = 60 Ω @ 5 mA | Lower leakage benefits ultra-low-power wake-on-event circuits; higher ZZ reduces regulation precision at low currents. | Choose MM3Z5V1T1G for battery life-critical applications where leakage dominates standby power budget. |
Compared with BZX584C5V1 and MM3Z5V1T1G, the MMSZ5231B offers superior thermal performance (340°C/W vs. ≥450°C/W) and lower Zener impedance (17 Ω vs. ≥60 Ω), making it optimal for stable regulation in industrial-grade PCBs with moderate power and thermal budgets.
Availability
MMSZ5231B is available at Aetrix Electronics and suitable for industrial sensor interfaces, microcontroller reset circuits, and analog signal conditioning requiring stable component supply and long-term lifecycle support.
Supply support for MMSZ5231B 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 supplier delivering energy-efficient, high-performance silicon solutions for automotive, industrial, cloud computing, and IoT applications.
The MMSZ5231B belongs to the MMSZ52xxB family of precision Zener diodes designed specifically for space-constrained, low-power voltage regulation and reference tasks in commercial and industrial environments.
FAQ
What is the nominal Zener voltage of the MMSZ5231B?
The MMSZ5231B has a nominal Zener voltage of 5.1 V, with a guaranteed range of 4.845 V to 4.935 V at test current IZ = 20 mA. This value is specified at 25°C ambient and reflects the center of its ±5% tolerance band. The MMSZ5231B maintains this regulation characteristic across its full operating temperature range.
Can the MMSZ5231B be used in forward-bias applications?
Yes, the MMSZ5231B can operate in forward bias with a maximum forward voltage of 0.9 V at 10 mA, per the datasheet. This allows dual-use as a low-VF clamp or ESD protection element in signal paths. However, its primary design intent remains reverse-bias Zener regulation, and forward conduction should be verified against thermal limits in sustained-current applications.
What is the maximum power dissipation rating for the MMSZ5231B?
The MMSZ5231B is rated for 500 mW maximum power dissipation at 25°C ambient temperature. Derating is required above 25°C at 1.47 mW/°C (based on RθJA = 340°C/W), limiting usable power to approximately 330 mW at 85°C board temperature. This rating assumes use on FR-4 with minimum recommended land pads as defined in the datasheet.
Does the MMSZ5231B have a specified junction temperature limit?
Yes, the MMSZ5231B has a maximum operating junction temperature (TJ) of +150°C. This limit governs safe operation under combined ambient temperature and self-heating conditions. To stay within this limit, designers must calculate junction temperature using TJ = TA + (PD × RθJA) and ensure the result does not exceed +150°C under worst-case load and ambient conditions.
Is the MMSZ5231B RoHS compliant and halogen-free?
Yes, the MMSZ5231B is RoHS compliant and halogen-free per ON Semiconductor's product change notices and material declarations. It meets JEDEC J-STD-609 Category 1 for bromine and chlorine content (<900 ppm each) and contains no lead, mercury, cadmium, hexavalent chromium, or polybrominated biphenyls (PBB)/polybrominated diphenyl ethers (PBDE).
MMSZ5231B Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- SOD-123
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 5.1 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 17 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 2 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
MMSZ5231B FAQ
1.How can I place an order for MMSZ5231B through Aetrix?
Please submit a Request for Quotation (RFQ) for MMSZ5231B 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 MMSZ5231B reliable?
The price and inventory of MMSZ5231B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMSZ5231B is usually 5 days.
3.What payment methods are accepted for MMSZ5231B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMSZ5231B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMSZ5231B?
MMSZ5231B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMSZ5231B 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 MMSZ5231B?
For technical support, including MMSZ5231B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMSZ5231B requirements.
6.How does Aetrix verify that MMSZ5231B is sourced from the original manufacturer or authorized distributors?
All MMSZ5231B 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 MMSZ5231B meets industry standards.
7.What is the process for return or replacement of MMSZ5231B?
All MMSZ5231B units undergo pre-shipment inspection (PSI). If there is an issue with MMSZ5231B, 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 MMSZ5231B part is unused and in its original packaging.
Return procedure for MMSZ5231B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMSZ5231B Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
-
BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
Tech Hub
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, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
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.
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.
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…
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…
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…
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 …
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…
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…
