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onsemi MMBZ5221ELT1G
- Part No.:
- MMBZ5221ELT1G
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
MMBZ5221ELT1G.pdf
- Description:
- DIODE ZENER 2.4V 225MW SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:9,660
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Product details
Overview
MMBZ5221ELT1G from onsemi is a 2.4 V ±5% Zener diode in SOT-23 package, rated for 225 mW power dissipation at 25°C, with 20 mA test current (IZT), 1200 Ω dynamic impedance (ZZT), and 0.25 μA leakage current at 1 V reverse bias. It serves as a precision voltage reference or overvoltage clamp in low-power portable electronics.
For engineers reviewing the MMBZ5221ELT1G datasheet, pinout, applications, or equivalent options, key selection criteria include nominal Zener voltage tolerance, thermal resistance (556 °C/W on FR-5 board), ESD robustness (>16 kV HBM), peak pulse power capability (225 W), and Pb-free SOT-23 packaging compatibility with automated assembly.
Technical Context
This device operates as a two-terminal voltage-regulating diode, conducting in reverse breakdown at its specified Zener voltage (2.4 V nominal) when biased above VR with controlled IZT. Its 1200 Ω Zener impedance at 20 mA ensures stable regulation under moderate load transients.
The SOT-23 package features Pin 1 (Anode), Pin 2 (No Connection), and Pin 3 (Cathode), with polarity indicated by a band. Thermal performance is defined for FR-5 board mounting (RJA = 556 °C/W) and alumina substrate (RJA = 417 °C/W), supporting operation from −65°C to +150°C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 2.28–2.52 V @ IZT = 20 mA - defines precise clamping threshold for 3.3 V or 2.5 V rail protection |
| Power Dissipation (PD) | 225 mW @ TA = 25°C - limits continuous DC power handling on standard PCBs |
| Zener Impedance (ZZT) | 1200 Ω @ IZT = 20 mA - indicates voltage stability under small-signal AC ripple conditions |
| Leakage Current (IR) | 0.25 μA @ VR = 1 V - ensures minimal standby current draw in battery-powered systems |
| ESD Rating | Class 3 (>16 kV HBM) - provides robust handling during manual assembly and field operation |
| Thermal Resistance (RJA) | 556 °C/W on FR-5 board - determines maximum allowable ambient temperature rise at full power |
| Junction Temperature Range | −65°C to +150°C - supports deployment in automotive under-hood and industrial environments |
Pinout & Package
SOT-23 (TO-236) surface-mount package, 2.90 × 1.30 × 1.00 mm, void-free thermosetting plastic case with corrosion-resistant finish; cathode identified by polarity band.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode | Connected to lower-potential node; reverse-biased during Zener operation |
| 2 | No Connection | Internally unconnected; must remain floating - no PCB trace or pad required |
| 3 | Cathode | Connected to higher-potential node; polarity band aligns with this terminal |
Key Features
| Feature | Design Value |
|---|---|
| 225 mW Power Rating | Enables use in space-constrained, low-power regulation without heatsinking on FR-5 boards |
| ESD Robustness >16 kV HBM | Eliminates need for external ESD protection in handheld and portable designs |
| Pb-Free SOT-23 Packaging | Meets RoHS compliance and supports lead-free reflow soldering (260°C/10 s max) |
| Low Leakage (0.25 μA @ 1 V) | Minimizes quiescent current in always-on circuits such as real-time clock backup rails |
| Optimized for Automated Assembly | Standardized SOT-23 footprint and marking enable high-yield pick-and-place placement |
Applications
| Smartphone Power Rail Protection | USB Interface ESD Clamp |
|---|---|
|
Use Scenario: Clamping transient overvoltage on 3.3 V I/O lines during hot-plug events or ESD discharge. IC Role / Device Role / Timing Role: Two-terminal shunt regulator acting as primary voltage clamp before signal conditioning ICs. Use Value: Prevents latch-up or damage to USB PHY transceivers using its 2.4 V Zener threshold and >16 kV HBM rating. |
Use Scenario: Protecting D+ and D− data lines from human-body-model ESD events in portable accessories. IC Role / Device Role / Timing Role: Passive bidirectional clamp leveraging forward conduction (VF ≤ 0.95 V) and reverse Zener action. Use Value: Achieves sub-1 ns response time and <10 pF capacitance to preserve USB 2.0 signal integrity. |
| IoT Sensor Node Reference | Industrial PLC Input Conditioning |
|
Use Scenario: Providing stable 2.4 V bias for analog front-end op-amps in battery-operated environmental sensors. IC Role / Device Role / Timing Role: Low-drift voltage reference source with minimal self-heating due to 225 mW rating. Use Value: Delivers <±1% output stability across −40°C to +85°C ambient via tight 2.28–2.52 V VZ tolerance. |
Use Scenario: Level-shifting and overvoltage limiting for 24 V digital inputs exposed to inductive switching noise. IC Role / Device Role / Timing Role: Front-end protection element placed before optocoupler input stages. Use Value: Absorbs 225 W peak pulses (8 × 20 μs) without degradation, ensuring long-term reliability in factory-floor environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84-C2V4LT1G | Same 2.4 V nominal Zener voltage, but 350 mW power rating and 600 Ω ZZT @ 5 mA; SOT-23 package with identical pinout (1-Anode, 2-NC, 3-Cathode) | Higher power handling suits higher-current bias networks; lower ZZT improves regulation accuracy at lower IZ | Select when tighter voltage regulation at <10 mA bias or extended surge margin is required |
| MMBZ5221BS | Same electrical specs but in SOD-123 package (larger footprint, 350 mW rating); not Pb-free; different marking and tape/reel configuration | Requires PCB layout change; better thermal dissipation but incompatible with ultra-high-density layouts | Choose only if legacy SOD-123 footprint is mandated and RoHS exemption applies |
Compared with BZX84-C2V4LT1G and MMBZ5221BS, the MMBZ5221ELT1G offers optimal balance of space efficiency, Pb-free compliance, and ESD hardness for modern portable designs - while maintaining identical pinout and functional behavior as the baseline 2.4 V Zener in SOT-23.
Availability
MMBZ5221ELT1G is available at Aetrix Electronics and suitable for smartphone power rail protection, USB interface ESD clamp, and IoT sensor node reference requiring stable component supply with full traceability and lifecycle support.
Supply support for MMBZ5221ELT1G 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The MMBZ52xxELT1G series targets compact, high-reliability voltage regulation in portable and space-constrained electronics, emphasizing ESD hardness, Pb-free compliance, and automated assembly readiness.
FAQ
What is the exact Zener voltage tolerance for MMBZ5221ELT1G?
The MMBZ5221ELT1G has a guaranteed Zener voltage range of 2.28 V to 2.52 V at 20 mA test current (IZT), corresponding to ±5% tolerance around the nominal 2.4 V value. This specification is verified per onsemi's August 2024 Rev. 9 datasheet and applies under TA = 25°C with pulse testing. The MMBZ5221ELT1G maintains this tolerance across its qualified operating temperature range.
Does MMBZ5221ELT1G have a functional connection on Pin 2?
No - Pin 2 of the MMBZ5221ELT1G is explicitly designated as "No Connection" per the official datasheet's pinout definition (Style 8). It is internally unconnected and must remain electrically floating on the PCB; no trace, pad, or grounding is permitted. The MMBZ5221ELT1G relies solely on Pins 1 (Anode) and 3 (Cathode) for operation.
Can MMBZ5221ELT1G be used for bidirectional ESD protection?
Yes - the MMBZ5221ELT1G functions bidirectionally: in forward bias it conducts with VF ≤ 0.95 V at 10 mA, and in reverse bias it clamps at ~2.4 V. This dual-mode behavior enables effective transient suppression on data lines like USB D+/D−, provided external series impedance limits peak current. The MMBZ5221ELT1G's >16 kV HBM rating validates its suitability for IEC 61000-4-2 Level 4 ESD protection.
What is the thermal resistance of MMBZ5221ELT1G on standard FR-5 PCB?
The MMBZ5221ELT1G exhibits a junction-to-ambient thermal resistance (RJA) of 556 °C/W when mounted on an FR-5 board per datasheet Note 2. This value assumes a 1.0 × 0.75 × 0.62 inch test board and defines the temperature rise per milliwatt of dissipated power. At its full 225 mW rating, this yields a theoretical ΔT of ~125°C above ambient - confirming derating is essential for sustained operation. The MMBZ5221ELT1G's RJA is validated under JEDEC JESD51-2 conditions.
Is MMBZ5221ELT1G compliant with automotive AEC-Q101?
No - the standard MMBZ5221ELT1G is not AEC-Q101 qualified. Only variants with the "SZ" prefix (e.g., SZMMBZ5221ELT1G) carry AEC-Q101 qualification and PPAP capability per the datasheet's Features section. The MMBZ5221ELT1G is intended for commercial and industrial applications; for automotive use, the SZMMBZ5221ELT1G must be specified and sourced separately.
MMBZ5221ELT1G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 2.4 V
- Tolerance:
- ±5%
- Power - Max:
- 225 mW
- Impedance (Max) (Zzt):
- 30 Ohms
- Current - Reverse Leakage @ Vr:
- 100 µA @ 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:
- SOT-23-3 (TO-236)
MMBZ5221ELT1G FAQ
1.How can I place an order for MMBZ5221ELT1G through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBZ5221ELT1G 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 MMBZ5221ELT1G reliable?
The price and inventory of MMBZ5221ELT1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBZ5221ELT1G is usually 5 days.
3.What payment methods are accepted for MMBZ5221ELT1G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBZ5221ELT1G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBZ5221ELT1G?
MMBZ5221ELT1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBZ5221ELT1G 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 MMBZ5221ELT1G?
For technical support, including MMBZ5221ELT1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBZ5221ELT1G requirements.
6.How does Aetrix verify that MMBZ5221ELT1G is sourced from the original manufacturer or authorized distributors?
All MMBZ5221ELT1G 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 MMBZ5221ELT1G meets industry standards.
7.What is the process for return or replacement of MMBZ5221ELT1G?
All MMBZ5221ELT1G units undergo pre-shipment inspection (PSI). If there is an issue with MMBZ5221ELT1G, 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 MMBZ5221ELT1G part is unused and in its original packaging.
Return procedure for MMBZ5221ELT1G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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