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Nexperia USA Inc. BZT52H-A18X
- Part No.:
- BZT52H-A18X
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SOD-123F
- Datasheet:
-
BZT52H-A18X.pdf
- Description:
- DIODE ZENER 18V 375MW SOD123F
- Quantity:
- Payment:
- Shipping:
Inventory:6,387
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Product details
Overview
BZT52H-A18X from Nexperia is a precision Zener voltage regulator diode in SOD123F package, rated for 18 V nominal breakdown voltage at 5 mA, ±1 % tolerance, and 830 mW total power dissipation. It provides stable reference voltage in low-power analog circuits, power supply feedback loops, and overvoltage protection stages.
For engineers reviewing the BZT52H-A18X datasheet, BZT52H-A18X pinout, BZT52H-A18X application, or BZT52H-A18X equivalent, key selection criteria include its tight 18.0 V ±1 % Zener voltage tolerance, low 170 Ω differential resistance at IZ = 5 mA, 12.6 mV/K temperature coefficient, and SOD123F surface-mount compatibility for space-constrained PCB layouts.
Technical Context
This Zener diode operates in reverse-biased breakdown mode to maintain a stable DC reference voltage across its terminals under varying load and input conditions. Its design targets low-noise, high-stability regulation in non-automotive industrial and consumer electronics where ±1 % initial accuracy and predictable thermal drift are required.
The device exhibits a typical differential resistance of 170 Ω at 5 mA test current, enabling effective ripple suppression in shunt-regulated supplies. Its junction-to-solder-point thermal resistance is 70 K/W, supporting reliable operation up to 150 °C junction temperature when mounted on standard FR4 PCB with 1 cm² cathode pad.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 17.82 V to 18.18 V at IZ = 5 mA - ensures precise 18 V reference with ±1 % initial accuracy for calibration-critical circuits |
| Differential Resistance (rdif) | 170 Ω max at IZ = 5 mA - limits output voltage variation under load changes, improving regulation stability |
| Temperature Coefficient (SZ) | 12.6 mV/K at IZ = 5 mA - quantifies voltage drift per degree Celsius, enabling accurate thermal compensation design |
| Total Power Dissipation (Ptot) | 830 mW at Tamb ≤ 25 °C - defines maximum continuous power handling on standard FR4 PCB with specified copper area |
| Forward Voltage (VF) | 0.9 V max at IF = 10 mA - specifies forward conduction drop for polarity-check or clamping use cases |
| Reverse Current (IR) | 0.05 μA max at VR = 14.4 V - confirms low leakage below breakdown, critical for battery-powered standby circuits |
| Junction Temperature (Tj) | −65 °C to +150 °C - establishes full operational range for industrial ambient environments |
Pinout & Package
SOD123F is a compact, flat-lead surface-mount plastic package measuring 3.6 mm × 1.7 mm × 1.0 mm (L × W × H), optimized for automated placement and reflow soldering on FR4 PCBs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Marked side) | Cathode (K) | Connected to higher-potential node in reverse-bias configuration; marking bar identifies this terminal for correct orientation during assembly |
| 2 | Anode (A) | Connected to lower-potential node (e.g., ground or return path); completes reverse-bias current path during Zener operation |
Key Features
| Feature | Design Value |
|---|---|
| ±1 % Zener voltage tolerance | Enables direct replacement in precision reference designs without recalibration or resistor trimming |
| 830 mW power rating on standard FR4 | Supports robust shunt regulation in 5–12 V auxiliary rails without heatsinking |
| SOD123F footprint compatibility | Matches IPC-7351B standard land pattern, ensuring manufacturability with mainstream pick-and-place equipment |
| 150 °C maximum junction temperature | Permits deployment in enclosed enclosures or near heat-generating components without derating concerns |
| Low 0.05 μA reverse leakage at 14.4 V | Minimizes quiescent current drain in always-on monitoring circuits and battery-backed systems |
Applications
| Power Supply Feedback Reference | Overvoltage Clamp Protection |
|---|---|
|
Use Scenario: Stabilizing output voltage in isolated flyback or buck-derived auxiliary supplies via optocoupler feedback loop. IC Role / Device Role / Timing Role: Provides precise 18 V reference to TL431-like shunt regulator IC, setting feedback threshold. Use Value: ±1 % VZ tolerance eliminates need for external trim resistors, reducing BOM count and calibration steps. |
Use Scenario: Protecting microcontroller I/O pins from transient surges exceeding 18 V in industrial sensor interfaces. IC Role / Device Role / Timing Role: Acts as passive shunt clamp, diverting excess energy to ground before damage occurs. Use Value: 170 Ω rdif ensures clamping voltage stays within safe margin (<19.5 V) even at 10 mA surge current. |
| ADC Reference Buffer | Low-Power Voltage Monitor |
|
Use Scenario: Generating stable 18 V reference for external ADC driver amplifiers in data acquisition modules. IC Role / Device Role / Timing Role: Supplies clean, low-drift bias point to op-amp stage preceding 16-bit SAR ADC. Use Value: 12.6 mV/K SZ allows predictable error modeling across −40 °C to +85 °C operating range. |
Use Scenario: Detecting brown-out conditions in 24 V DC-powered instrumentation by comparing against 18 V threshold. IC Role / Device Role / Timing Role: Serves as fixed reference input to comparator with hysteresis network. Use Value: 0.05 μA IR at 14.4 V ensures <100 nA total current draw, extending battery life in portable units. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZT52H-B18 | ±2 % VZ tolerance (17.6–18.4 V), same SOD123F package and 830 mW rating | Acceptable where system-level calibration compensates for wider initial tolerance | Select when cost sensitivity outweighs need for ±1 % accuracy and no post-assembly trimming is planned |
| MMSZ5245B | 18 V nominal, ±5 % tolerance, SOD-123 package, 500 mW Ptot, higher rdif (230 Ω) | Lower power handling and looser tolerance limit use to non-critical biasing or indicator circuits | Choose only for legacy designs or cost-driven replacements where 830 mW headroom and 170 Ω rdif are not required |
Compared with BZT52H-B18 and MMSZ5245B, the BZT52H-A18X delivers superior initial accuracy and lower dynamic impedance-critical for closed-loop regulation and precision sensing-while maintaining identical board footprint and thermal performance.
Availability
BZT52H-A18X is available at Aetrix Electronics and suitable for power supply feedback reference, overvoltage clamp protection, and low-power voltage monitor applications requiring stable component supply and consistent parametric performance across production batches.
Supply support for BZT52H-A18X 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
Nexperia is a global semiconductor expert delivering high-performance, reliable discrete, logic, and MOSFET devices with focus on efficiency, miniaturization, and manufacturability.
The BZT52H series belongs to Nexperia's general-purpose Zener diode product line, engineered for stable voltage reference and regulation in cost-sensitive, high-volume industrial and consumer electronics-not automotive-qualified applications.
FAQ
What is the guaranteed Zener voltage range for BZT52H-A18X at 5 mA test current?
The guaranteed Zener voltage range is 17.82 V to 18.18 V at IZ = 5 mA, reflecting its ±1 % tolerance specification. This range is validated per Nexperia's Rev. 7 datasheet (January 2023) and applies under Tj = 25 °C conditions with pulse testing (tp ≤ 300 μs).
Can BZT52H-A18X be used in automotive applications?
No. The BZT52H-A18X is explicitly designated as non-automotive qualified per Nexperia's revision history (Rev. 7, January 2023). It lacks AEC-Q200 qualification and has not undergone automotive-grade stress testing or reliability validation.
What is the maximum allowable forward current for BZT52H-A18X?
The absolute maximum forward current is 250 mA, as defined in Table 5 (Limiting Values) of the datasheet. However, continuous forward conduction is not its intended operating mode; it is designed for reverse-bias Zener regulation.
How does thermal resistance affect BZT52H-A18X's power handling in real PCB layouts?
With Rth(j-sp) = 70 K/W (junction-to-solder-point), a 500 mW dissipation raises junction temperature by ~35 °C above solder point temperature. On a standard FR4 board with 1 cm² cathode pad, this enables full 830 mW operation only if ambient remains ≤25 °C and board copper acts as effective heat spreader.
BZT52H-A18X Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZT52H
- Package/Case:
- SOD-123F
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 18 V
- Tolerance:
- ±1%
- Power - Max:
- 375 mW
- Impedance (Max) (Zzt):
- 20 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 12.6 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-123F
BZT52H-A18X FAQ
1.How can I place an order for BZT52H-A18X through Aetrix?
Please submit a Request for Quotation (RFQ) for BZT52H-A18X 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 BZT52H-A18X reliable?
The price and inventory of BZT52H-A18X are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZT52H-A18X is usually 5 days.
3.What payment methods are accepted for BZT52H-A18X?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZT52H-A18X transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZT52H-A18X?
BZT52H-A18X orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZT52H-A18X 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 BZT52H-A18X?
For technical support, including BZT52H-A18X datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZT52H-A18X requirements.
6.How does Aetrix verify that BZT52H-A18X is sourced from the original manufacturer or authorized distributors?
All BZT52H-A18X 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 BZT52H-A18X meets industry standards.
7.What is the process for return or replacement of BZT52H-A18X?
All BZT52H-A18X units undergo pre-shipment inspection (PSI). If there is an issue with BZT52H-A18X, 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 BZT52H-A18X part is unused and in its original packaging.
Return procedure for BZT52H-A18X:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZT52H-A18X Tags
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MMSZ5231B-7-F
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BZX84C3V3LT1G
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MMSZ5245BS-7-F
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MMSZ4682T1G
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MM5Z5V1ST1G
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SMAJ4744A-TP
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