My Inquiry
My Account
onsemi MMBZ5248ELT1
- Part No.:
- MMBZ5248ELT1
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
MMBZ5248ELT1.pdf
- Description:
- DIODE ZENER 18V 225MW SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:7,294
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MMBZ5248ELT1 from onsemi is a 18 V ±5% Zener voltage regulator diode in SOT-23 package, rated for 225 mW power dissipation at 25°C, with 7 mA test current (IZT), 21 Ω dynamic impedance (ZZT), and 0.1 µA reverse leakage at 14 V (VR). It serves as a precision voltage reference or overvoltage clamp in low-power portable electronics.
For engineers reviewing the MMBZ5248ELT1 datasheet, pinout, applications, or equivalent options, key selection criteria include nominal Zener voltage tolerance, thermal resistance (556 °C/W on FR-5), ESD robustness (>16 kV HBM), peak pulse power (225 W), and SOT-23 footprint compatibility for high-density PCB layouts.
Technical Context
This device operates in reverse-biased Zener breakdown mode to maintain stable voltage across its terminals under varying load or supply conditions. Its 18 V nominal regulation point falls within the positive temperature coefficient range per Figure 1, ensuring predictable drift behavior above ~6 V.
The SOT-23 package features three terminals - anode (Pin 1), no-connect (Pin 2), and cathode (Pin 3) - enabling unidirectional clamping with polarity band identification. Thermal performance is specified for both FR-5 board (225 mW) and alumina substrate (300 mW), supporting design flexibility in thermally constrained environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 17.1–18.9 V @ IZT = 7 mA; defines stable regulation window for reference or protection circuits |
| Power Dissipation (PD) | 225 mW @ TA = 25°C on FR-5 board; sets maximum continuous DC power handling before thermal derating |
| Zener Impedance (ZZT) | 21 Ω @ IZT = 7 mA; determines output voltage variation under changing load current |
| Reverse Leakage (IR) | 0.1 µA @ VR = 14 V; ensures minimal standby current in voltage-sense or battery-backed applications |
| ESD Rating | Class 3 (>16 kV) per Human Body Model; supports robust handling in automated assembly and end-use environments |
| Junction Temp Range | −65°C to +150°C; enables operation in extended industrial and automotive ambient conditions |
| Package | SOT-23 (TO-236); 2.90 × 1.30 × 1.00 mm footprint ideal for space-constrained portable designs |
Pinout & Package
SOT-23 plastic surface-mount package with void-free thermosetting case, corrosion-resistant finish, and UL 94 V-0 flammability rating. Cathode identified by polarity band. Maximum soldering temperature: 260°C for 10 seconds.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode | Connected to lower-potential node in reverse-bias configuration; required for proper Zener conduction path |
| 2 | No Connection | Internally unconnected; must remain floating - no PCB trace or pad connection permitted |
| 3 | Cathode | Connected to higher-potential node; polarity band aligns with this terminal for visual orientation |
Key Features
| Feature | Design Value |
|---|---|
| 225 mW Power Rating | Enables use in compact battery-powered systems without external heat sinking |
| ESD Robustness >16 kV HBM | Reduces need for additional ESD protection components in handheld interface circuits |
| Pb-Free Construction | Complies with RoHS Directive 2011/65/EU and JEDEC J-STD-609A Class 3 moisture sensitivity |
| Peak Pulse Power 225 W | Supports transient suppression of short-duration surges (8 × 20 µs waveform) without failure |
| Small Outline Package | Facilitates automated placement and reflow on high-density PCBs with <1.3 mm width constraint |
Applications
| Smartphone Power Rail Clamp | USB Port Overvoltage Protection |
|---|---|
Use Scenario: Clamping 5 V USB input rail against ESD events or adapter overvoltage during hot-plug. IC Role / Device Role / Timing Role: Zener diode operating in reverse breakdown to shunt excess voltage to ground. Use Value: Limits voltage excursion to ≤18.9 V, protecting downstream USB PHY and PMIC from damage while consuming <0.1 µA standby current. |
Use Scenario: Protecting microcontroller I/O pins connected to external sensors powered via shared 3.3 V rail. IC Role / Device Role / Timing Role: Low-leakage voltage reference providing stable bias for analog comparators monitoring rail integrity. Use Value: Maintains 18 V regulation tolerance (±5%) across −40°C to +85°C, enabling accurate fault detection without calibration drift. |
| Wearable Battery Voltage Monitor | Industrial Sensor Signal Conditioning |
Use Scenario: Providing reference voltage for ADC measurement of Li-ion cell voltage in fitness trackers. IC Role / Device Role / Timing Role: Precision Zener used as stable excitation source for ratiometric sensing circuitry. Use Value: Delivers 18 V reference with 21 Ω dynamic impedance, minimizing measurement error due to supply ripple or load variation. |
Use Scenario: Stabilizing bias voltage for op-amp input stages in 4–20 mA loop transmitters exposed to EMI. IC Role / Device Role / Timing Role: Low-capacitance (<5 pF at 50% VZ) shunt regulator filtering high-frequency noise on supply rails. Use Value: Suppresses RF interference above 100 MHz while maintaining <0.1 µA leakage, preserving loop accuracy and long-term stability. |
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-C18LT1G | Same 18 V nominal Zener, but 300 mW rating and 40 Ω ZZT @ 5 mA; slightly higher leakage (1 µA @ 14 V) | Higher power handling suits moderate-current bias networks; less suitable for ultra-low-leakage sensing | Select when board layout allows larger thermal relief or when tighter ZZT tolerance is not required |
| MMBZ5248BS | Same electrical specs but in SOD-323 package (1.7 × 1.25 × 0.95 mm); 200 mW rating; identical pinout mapping (Anode/NC/Cathode) | Smaller footprint benefits ultra-compact wearables; reduced power margin requires careful thermal analysis | Choose for space-critical designs where SOT-23 is too large, and 200 mW suffices for target operating conditions |
Compared with BZX84-C18LT1G and MMBZ5248BS, the MMBZ5248ELT1 offers optimal balance of low leakage (0.1 µA), tight Zener tolerance (±5%), and proven SOT-23 manufacturability - making it preferred for portable electronics requiring reliable, repeatable voltage clamping without thermal compromise.
Availability
MMBZ5248ELT1 is available at Aetrix Electronics and suitable for smartphone power rail clamp, USB port overvoltage protection, and wearable battery voltage monitor applications requiring stable component supply and full RoHS compliance.
Supply support for MMBZ5248ELT1 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 (formerly ON Semiconductor) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The MMBZ52xxELT1G series was designed specifically for space-constrained, low-power voltage regulation and transient suppression in portable electronics - emphasizing small footprint, high ESD immunity, and consistent Zener performance across temperature.
FAQ
What is the exact Zener voltage tolerance for MMBZ5248ELT1?
The MMBZ5248ELT1 has a guaranteed Zener voltage range of 17.1 V to 18.9 V at IZT = 7 mA and TA = 25°C, corresponding to a ±5% tolerance around the nominal 18 V value. This specification is verified per onsemi's Electrical Characteristics table on page 2 of the August 2024 Rev. 9 datasheet and applies directly to the MMBZ5248ELT1/T1G ordering variant.
Does MMBZ5248ELT1 have a functional pin 2 connection?
No - pin 2 of the MMBZ5248ELT1 is internally not connected (NC), as confirmed in the Electrical Characteristics section and Pinout diagram (Style 8) on page 2 of the datasheet. It must remain unconnected on the PCB; routing or soldering to pin 2 may cause assembly defects or functional failure of the MMBZ5248ELT1.
Can MMBZ5248ELT1 be used for bidirectional ESD protection?
No - the MMBZ5248ELT1 is a unidirectional Zener diode configured only for reverse-bias operation (anode-to-ground, cathode-to-rail). It does not provide symmetrical clamping and lacks forward conduction capability for negative transients. For bidirectional protection, a dedicated TVS array such as ESD9X5.0ST5G must be used instead of the MMBZ5248ELT1.
What is the thermal resistance junction-to-ambient for MMBZ5248ELT1 on standard PCB?
The thermal resistance junction-to-ambient (RJA) for MMBZ5248ELT1 is 556 °C/W when mounted on FR-5 board, as specified in the Maximum Ratings table on page 1 of the datasheet. This value assumes standard 1.0 × 0.75 × 0.62 inch test board dimensions and defines the temperature rise per milliwatt of dissipated power under natural convection conditions.
Is MMBZ5248ELT1 qualified for automotive applications?
The base MMBZ5248ELT1 is not AEC-Q101 qualified; however, the SZMMBZ5248ELT1G variant - which shares identical electrical and mechanical specifications - is explicitly qualified per AEC-Q101 and PPAP capable, as noted in the Features section. For automotive use, specify SZMMBZ5248ELT1G rather than MMBZ5248ELT1 to ensure compliance.
MMBZ5248ELT1 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):
- 18 V
- Tolerance:
- ±5%
- Power - Max:
- 225 mW
- Impedance (Max) (Zzt):
- 21 Ohms
- Current - Reverse Leakage @ Vr:
- 100 nA @ 14 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)
MMBZ5248ELT1 FAQ
1.How can I place an order for MMBZ5248ELT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBZ5248ELT1 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 MMBZ5248ELT1 reliable?
The price and inventory of MMBZ5248ELT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBZ5248ELT1 is usually 5 days.
3.What payment methods are accepted for MMBZ5248ELT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBZ5248ELT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBZ5248ELT1?
MMBZ5248ELT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBZ5248ELT1 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 MMBZ5248ELT1?
For technical support, including MMBZ5248ELT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBZ5248ELT1 requirements.
6.How does Aetrix verify that MMBZ5248ELT1 is sourced from the original manufacturer or authorized distributors?
All MMBZ5248ELT1 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 MMBZ5248ELT1 meets industry standards.
7.What is the process for return or replacement of MMBZ5248ELT1?
All MMBZ5248ELT1 units undergo pre-shipment inspection (PSI). If there is an issue with MMBZ5248ELT1, 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 MMBZ5248ELT1 part is unused and in its original packaging.
Return procedure for MMBZ5248ELT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMBZ5248ELT1 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…
