My Inquiry
My Account
Diodes Incorporated MMBZ5257BW-7
- Part No.:
- MMBZ5257BW-7
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
MMBZ5257BW-7.pdf
- Description:
- DIODE ZENER 33V 200MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:9,152
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MMBZ5257BW-7 from Diodes Incorporated is a 33 V, 200 mW surface-mount Zener diode in SOT323 package, rated for 3.8 mA test current, with 58 Ω zener impedance at 1 kHz and 0.1 μA reverse leakage at 25 V, used for precision voltage regulation and overvoltage protection in low-power analog sensor interfaces.
For engineers reviewing the MMBZ5257BW-7 datasheet, MMBZ5257BW-7 pinout, MMBZ5257BW-7 application, or MMBZ5257BW-7 equivalent, key selection criteria include nominal zener voltage tolerance (±3.5%), thermal resistance (625 °C/W), AEC-Q101 qualification, green halogen-free construction, and SOT323 footprint compatibility with automated assembly.
Technical Context
This Zener diode operates in reverse breakdown to maintain stable reference voltage under varying load and temperature conditions. Its 33 V nominal zener voltage is specified at 3.8 mA test current, with 58 Ω dynamic impedance measured at 1 kHz, ensuring predictable regulation performance in feedback networks.
The device is qualified to AEC-Q101 standards and built in a lead-free, halogen-free SOT323 package with matte tin-plated terminals. It exhibits 0.1 μA maximum reverse leakage at VR = 25 V and derates linearly above +25°C per the published power derating curve.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage | 33 V nominal, 31.35–34.65 V range at 3.8 mA - defines regulation setpoint in voltage-reference circuits |
| Power Dissipation | 200 mW at +25°C - limits continuous power handling on standard FR4 PCB with recommended pad layout |
| Zener Impedance | 58 Ω at 1 kHz - determines AC regulation stability and noise rejection in feedback paths |
| Reverse Leakage | 0.1 μA max at 25 V - ensures minimal quiescent current draw in battery-powered sensing nodes |
| Thermal Resistance | 625 °C/W junction-to-ambient - dictates temperature rise under load; requires thermal-aware PCB layout |
| Package | SOT323 - 2.1 mm × 1.3 mm footprint compatible with high-density routing and reflow soldering |
Pinout & Package
Package: SOT323 - three-terminal surface-mount plastic case with cathode-marked top-side marking (YM date code + KM2); dimensions: 2.10 mm × 1.30 mm × 0.90 mm (L × W × H), weight ≈ 0.006 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener cathode reference node | Connected to lower-potential side in shunt regulation; forms ground-referenced voltage clamp |
| Cathode | Zener breakdown terminal / regulation output node | Connected to regulated rail; sinks current to maintain 33 V across load when input exceeds threshold |
| Case / Heat Slug | Non-electrical mechanical termination | Not internally connected; serves only as mechanical anchor and thermal path to PCB copper |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified reliability | Validated for automotive-grade operation across –65°C to +150°C ambient range |
| Green halogen- and antimony-free construction | Meets <900 ppm Br, <900 ppm Cl, <1000 ppm Sb; UL 94V-0 flammability rating |
| Automated-assembly optimized | SOT323 package with matte tin finish; solderable per MIL-STD-202, Method 208 |
| Low reverse leakage | 0.1 μA max at 25 V enables microamp-level standby current in portable systems |
Applications
| Industrial Sensor Signal Conditioning | Automotive Body Control Module (BCM) Voltage Clamp |
|---|---|
Use Scenario: Stabilizing reference voltage for 12-bit ADCs in temperature/humidity transmitters operating from 3.3 V rails. IC Role / Device Role / Timing Role: Shunt voltage regulator providing precise 33 V reference for op-amp biasing and ADC full-scale calibration. Use Value: Tight 31.35–34.65 V tolerance and 58 Ω impedance ensure <0.5% reference drift over temperature and load variation. | Use Scenario: Protecting LIN bus interface ICs from load-dump transients up to 40 V in 12 V vehicle electrical systems. IC Role / Device Role / Timing Role: Overvoltage clamp limiting rail voltage to 33 V during transient events, preventing latch-up in downstream logic. Use Value: AEC-Q101 qualification and 200 mW surge capability support reliable clamping without degradation after repeated 100 ms pulses. |
| IoT Edge Node Power Supervision | Medical Wearable Battery Monitoring |
Use Scenario: Monitoring supply voltage in BLE-enabled environmental monitors powered by coin-cell batteries. IC Role / Device Role / Timing Role: Low-leakage voltage detector enabling wake-up when VDD exceeds 33 V threshold (via comparator input). Use Value: 0.1 μA reverse leakage preserves battery life over multi-year deployments while maintaining accurate trip point. | Use Scenario: Providing stable reference for analog front-end amplifiers measuring ECG electrode offset voltages. IC Role / Device Role / Timing Role: Precision shunt regulator establishing clean 33 V reference for instrumentation amplifier gain-setting resistors. Use Value: Green, RoHS-compliant construction meets IEC 60601-1 material restrictions for patient-connected devices. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84-C33-7-F | Same 33 V nominal, but 350 mW rating and SOT23 package; 60 Ω ZZT at 5 mA | Higher power handling supports higher-current clamping; larger SOT23 footprint may limit board density | Select when >200 mW dissipation or legacy SOT23 layout reuse is required |
| MMSZ5257T1G | 33 V nominal, 500 mW rating, SOD-123 package; 30 Ω ZZT at 20 mA | Lower impedance improves regulation accuracy but requires higher test current; larger package increases area use | Select when tighter regulation (<1% error) and higher surge tolerance are prioritized over size |
Compared with BZX84-C33-7-F and MMSZ5257T1G, MMBZ5257BW-7 offers optimal balance of ultra-small SOT323 footprint, AEC-Q101 qualification, and green compliance-making it preferred for space-constrained automotive and portable medical designs where 200 mW suffices.
Availability
MMBZ5257BW-7 is available at Aetrix Electronics and suitable for industrial sensor signal conditioning, automotive body control module voltage clamp, and IoT edge node power supervision requiring stable component supply and long-term lifecycle assurance.
Supply support for MMBZ5257BW-7 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.
The MMBZ52xxBW series belongs to Diodes' precision Zener diode product line, engineered specifically for space-constrained, high-reliability voltage reference and protection applications in automotive, industrial, and portable electronics.
FAQ
What is the maximum reverse voltage that can be continuously applied without breakdown?
The MMBZ5257BW-7 has a nominal zener voltage of 33 V, with a guaranteed breakdown range of 31.35 V to 34.65 V at 3.8 mA. Continuous reverse voltage below the minimum breakdown voltage (31.35 V) will not cause conduction; operation above this range initiates controlled breakdown. Do not exceed 200 mW power dissipation under any condition.
Is MMBZ5257BW-7 suitable for use in automotive applications?
Yes - it is explicitly qualified to AEC-Q101 standards for high-reliability automotive use, with operating temperature range from –65°C to +150°C, green halogen-free construction, and robust moisture sensitivity level (MSL 1). It is commonly deployed in BCMs, infotainment power rails, and sensor modules.
How does the SOT323 package affect thermal performance?
The SOT323 package has a junction-to-ambient thermal resistance of 625 °C/W on standard FR4 with recommended pad layout. This means a 200 mW dissipation causes ~125°C junction rise above ambient. For sustained operation, keep ambient temperature ≤ +25°C or reduce power derating per Figure 1 in the datasheet.
Can MMBZ5257BW-7 replace older MMBZ5257B variants?
Yes - the "-7" suffix denotes tape-and-reel packaging (3000 units/reel) and is functionally identical to MMBZ5257B in electrical and thermal specifications. The "W" denotes green molding compound; both share identical zener characteristics, marking, and AEC-Q101 qualification.
MMBZ5257BW-7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Voltage - Zener (Nom) (Vz):
- 33 V
- Tolerance:
- ±5%
- Power - Max:
- 200 mW
- Impedance (Max) (Zzt):
- 58 Ohms
- Current - Reverse Leakage @ Vr:
- 100 nA @ 25 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- -65°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
MMBZ5257BW-7 FAQ
1.How can I place an order for MMBZ5257BW-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBZ5257BW-7 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 MMBZ5257BW-7 reliable?
The price and inventory of MMBZ5257BW-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBZ5257BW-7 is usually 5 days.
3.What payment methods are accepted for MMBZ5257BW-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBZ5257BW-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBZ5257BW-7?
MMBZ5257BW-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBZ5257BW-7 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 MMBZ5257BW-7?
For technical support, including MMBZ5257BW-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBZ5257BW-7 requirements.
6.How does Aetrix verify that MMBZ5257BW-7 is sourced from the original manufacturer or authorized distributors?
All MMBZ5257BW-7 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 MMBZ5257BW-7 meets industry standards.
7.What is the process for return or replacement of MMBZ5257BW-7?
All MMBZ5257BW-7 units undergo pre-shipment inspection (PSI). If there is an issue with MMBZ5257BW-7, 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 MMBZ5257BW-7 part is unused and in its original packaging.
Return procedure for MMBZ5257BW-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMBZ5257BW-7 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
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
