My Inquiry
My Account
Diodes Incorporated MMBZ5255BT-7-F
- Part No.:
- MMBZ5255BT-7-F
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Zener Diodes
- Package:
- SOT-523
- Datasheet:
-
MMBZ5255BT-7-F.pdf
- Description:
- DIODE ZENER 28V 150MW SOT523
- Quantity:
- Payment:
- Shipping:
Inventory:6,320
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MMBZ5255BT-7-F from Diodes Incorporated is a 28 V, 150 mW surface-mount Zener diode in SOT-523 package, with nominal Zener voltage 28 V (min 26.6 V, max 29.4 V), test current 4.5 mA, and maximum Zener impedance 44 Ω at 1 kHz; used for precision voltage regulation and overvoltage protection in low-power sensor signal conditioning circuits.
For engineers reviewing the MMBZ5255BT-7-F datasheet, MMBZ5255BT-7-F pinout, MMBZ5255BT-7-F application, or MMBZ5255BT-7-F equivalent, key selection criteria include Zener voltage tolerance, dynamic impedance at operating current, power derating above 25°C, reverse leakage at rated VR, and SOT-523 thermal resistance (833 °C/W) for compact PCB layouts.
Technical Context
This Zener diode employs planar die construction for stable breakdown characteristics and low temperature coefficient. It operates within -65°C to +150°C ambient range and delivers regulated voltage under reverse-biased conditions with specified IZT = 4.5 mA and VR = 21 V.
Its ultra-small SOT-523 footprint supports high-density automated assembly, and lead-free matte tin plating ensures RoHS compliance. The device exhibits 0.1 µA reverse leakage at VR = 21 V and maintains ≤44 Ω dynamic impedance at 1 kHz, critical for noise-sensitive reference applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (Nom) | 28 V - precise DC reference voltage at 4.5 mA test current |
| Zener Voltage Range | 26.6 V to 29.4 V - ±5% tolerance band defining regulation accuracy |
| Power Dissipation | 150 mW - maximum steady-state power at 25°C ambient, derates linearly above |
| Zener Impedance | 44 Ω @ 1 kHz - AC impedance affecting regulation stability under varying load |
| Reverse Leakage | 0.1 µA @ 21 V - minimal parasitic current preserving low-power standby integrity |
| Thermal Resistance | 833 °C/W - junction-to-ambient value guiding PCB copper area requirements |
| Package | SOT-523 - 0.002 g, 1.6 mm × 0.8 mm footprint enabling miniaturized designs |
Pinout & Package
SOT-523 is a 3-terminal ultra-small plastic package with anode and cathode leads and no case connection. Polarity is marked by a cathode band on the top surface.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Pin 1) | Forward conduction terminal | Connected to lower potential side in reverse-bias regulation configuration |
| Cathode (Pin 2) | Zener breakdown terminal | Connected to higher potential side; defines regulated output node when reverse-biased |
| Case / Not Connected | Non-electrical mechanical support | No internal connection; serves only as structural anchor and thermal path |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-small SOT-523 footprint | Enables placement in space-constrained IoT sensor nodes and wearables |
| Planar die construction | Ensures repeatable Zener voltage distribution and long-term parametric stability |
| 150 mW power rating with 833 °C/W RθJA | Supports operation up to +85°C ambient with minimal board copper area |
| 0.1 µA IR @ 21 V | Maintains microamp-level system sleep current in battery-powered devices |
Applications
| Voltage Reference for ADC Biasing | Overvoltage Clamp in RS-485 Receivers |
|---|---|
Use Scenario: Provides stable 28 V reference for 12-bit SAR ADC input scaling in industrial analog front-ends. IC Role / Device Role / Timing Role: Zener diode operating in reverse breakdown to fix reference node voltage independent of supply variation. Use Value: Achieves <±0.5% full-scale error contribution due to tight 26.6–29.4 V tolerance and low 44 Ω dynamic impedance. | Use Scenario: Clamps transient surges on RS-485 bus lines to protect receiver inputs during ESD events. IC Role / Device Role / Timing Role: Fast-acting shunt protector absorbing >1 kW surge pulses per Fig. 6 (1 ms pulse width). Use Value: Limits line voltage to ≤29.4 V during transients while adding <0.5 pF capacitance to preserve signal integrity. |
| Low-Power Sensor Excitation Supply | Microcontroller Reset Circuit Voltage Monitor |
Use Scenario: Supplies regulated excitation voltage to piezoresistive pressure sensors in portable medical devices. IC Role / Device Role / Timing Role: Zener-based shunt regulator delivering stable bias current with minimal quiescent draw. Use Value: Draws only 4.5 mA at regulation point and contributes <1 µA total leakage, extending battery life. | Use Scenario: Monitors 3.3 V rail for brown-out detection using resistor divider into MCU reset pin. IC Role / Device Role / Timing Role: Precision threshold detector via voltage divider feeding into comparator input. Use Value: Enables accurate 2.94 V trip point (10% below 3.3 V) with ±5% Zener tolerance and negligible tempco drift. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX584C27LT1G | 27 V nominal, SOD-523 package, 200 mW rating, 30 Ω Zzt | Higher power and lower impedance but 1 V lower Zener voltage | Select when tighter regulation (<30 Ω) and higher surge margin are required |
| MMBZ5254BT-7-F | 27 V nominal, identical SOT-523 package and 150 mW rating, 41 Ω Zzt | 1 V lower Zener voltage with slightly lower dynamic impedance | Choose for legacy compatibility where 27 V reference suffices and lower impedance improves stability |
Compared with MMBZ5255BT-7-F, BZX584C27LT1G offers better surge handling and lower impedance but requires layout adaptation for SOD-523; MMBZ5254BT-7-F provides drop-in voltage reduction with identical thermal and assembly behavior.
Availability
MMBZ5255BT-7-F is available at Aetrix Electronics and suitable for industrial sensor interfaces, portable medical instrumentation, and RS-485 communication modules requiring stable component supply and RoHS-compliant sourcing.
Supply support for MMBZ5255BT-7-F 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, serving automotive, industrial, computing, and consumer markets with high-reliability components.
This device belongs to the MMBZ52xxBT Zener series designed specifically for space-constrained, low-power voltage regulation and protection in surface-mount applications demanding consistent parametric performance and automated assembly compatibility.
FAQ
What is the maximum reverse voltage (VR) this Zener diode can withstand before breakdown?
The MMBZ5255BT-7-F has a rated reverse voltage (VR) of 21 V, defined as the voltage at which reverse leakage remains ≤0.1 µA. Breakdown occurs at its nominal Zener voltage of 28 V under 4.5 mA test current, with guaranteed range 26.6–29.4 V. Operation above 21 V in non-breakdown mode risks exceeding leakage limits.
How does thermal derating affect usable power at 85°C ambient?
At 85°C ambient, the device's usable power drops to approximately 75 mW. This follows the linear derating curve in Figure 1: (150 mW) × [1 − (85 − 25)/833] ≈ 75 mW. Board layout must provide adequate copper area to maintain junction temperature below 150°C under this condition.
Is this Zener diode suitable for use in a precision 28 V reference circuit?
Yes, but with design constraints: its ±5% voltage tolerance (26.6–29.4 V) and 44 Ω dynamic impedance require buffering or trimming for sub-1% accuracy. It is appropriate for cost-sensitive, moderate-accuracy references where external calibration or feedback compensation is applied.
Can MMBZ5255BT-7-F replace MMBZ5254BT-7-F without circuit modification?
No-though both share SOT-523 packaging and 150 mW rating, MMBZ5255BT-7-F has 28 V nominal Zener voltage versus 27 V for MMBZ5254BT-7-F. A 1 V difference affects voltage divider ratios, clamp thresholds, and reference levels; revalidation of regulation point and margin is required.
MMBZ5255BT-7-F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- SOT-523
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 28 V
- Tolerance:
- ±5%
- Power - Max:
- 150 mW
- Impedance (Max) (Zzt):
- 44 Ohms
- Current - Reverse Leakage @ Vr:
- 100 nA @ 21 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-523
MMBZ5255BT-7-F FAQ
1.How can I place an order for MMBZ5255BT-7-F through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBZ5255BT-7-F 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 MMBZ5255BT-7-F reliable?
The price and inventory of MMBZ5255BT-7-F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBZ5255BT-7-F is usually 5 days.
3.What payment methods are accepted for MMBZ5255BT-7-F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBZ5255BT-7-F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBZ5255BT-7-F?
MMBZ5255BT-7-F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBZ5255BT-7-F 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 MMBZ5255BT-7-F?
For technical support, including MMBZ5255BT-7-F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBZ5255BT-7-F requirements.
6.How does Aetrix verify that MMBZ5255BT-7-F is sourced from the original manufacturer or authorized distributors?
All MMBZ5255BT-7-F 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 MMBZ5255BT-7-F meets industry standards.
7.What is the process for return or replacement of MMBZ5255BT-7-F?
All MMBZ5255BT-7-F units undergo pre-shipment inspection (PSI). If there is an issue with MMBZ5255BT-7-F, 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 MMBZ5255BT-7-F part is unused and in its original packaging.
Return procedure for MMBZ5255BT-7-F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMBZ5255BT-7-F 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…
