BZT52B15-E3-18 - 15V 410mW ±2% SOD-123 Zener Diode | Vishay
MPN: BZT52B15-E3-18 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.1337 | $0.13 |
| 10 | $0.13 | $1.30 |
| 100 | $0.1 | $10.00 |
| 500 | $0.085 | $42.50 |
| 1,000 | $0.07 | $70.00 |
BZT52B15-E3-18 Overview
A Zener diode is a specialized silicon pn-junction device engineered to operate in the reverse-breakdown region, where it maintains a nearly fixed cathode-to-anode voltage over a wide range of reverse currents. Diodes in the BZT52B family serve as low-power voltage references, voltage clamps, and over-voltage protectors, sitting within the discrete semiconductor hierarchy: Zener diode → diode → discrete semiconductor → electronic component. They are the workhorse building block of analog front-ends, MCU rails, and protection networks.
The BZT52B15-E3-18 delivers a nominal 15 V reference with ±2% tolerance at the specified test current, 410 mW total power dissipation on the recommended 40 mm × 40 mm × 0.022 L pitch PCB footprint, and a low-leakage reverse current suitable for low-power applications. Its planar silicon construction provides stable temperature behavior and long-term reliability in commercial and industrial environments.
Typical applications include voltage reference for ADCs and DACs, over-voltage protection for microcontroller I/O lines, precision regulated supplies, and signal clamping in sensor-conditioning circuits. Its SOD-123 outline allows direct substitution in tight PCB layouts where a 15 V rail must be derived locally without a switching regulator.
When designing with this part, derate power linearly above 25 °C ambient and verify the dynamic Zener impedance at the actual operating current — Zener voltage shifts slightly with current and must be carefully tuned to the application. Place the diode close to the protected node and keep trace inductance short to maximize clamping effectiveness.
This page synthesizes distributor stock and pricing from leading distributors (DigiKey, Mouser, Arrow, LCSC, TTI), pin-compatible drop-in alternatives from Vishay's own BZT52B family and cross-brand sources (Nexperia, MCC, Diotec), and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for BZT52B15-E3-18 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
BZT52B15-E3-08
✅ Drop-In📋 Reference alternative (not in catalog)
BZT52B15-HE3-18
✅ Drop-In📋 Reference alternative (not in catalog)
BZT52B16-E3-18
✅ Drop-In📋 Reference alternative (not in catalog)
BZT52B14-E3-18
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
BZT52-B15
✅ Drop-In📋 Reference alternative (not in catalog)
BZT52B15-TP
✅ Drop-In📋 Reference alternative (not in catalog)
BZT52B15
✅ Drop-In📋 Reference alternative (not in catalog)
BZT52B15-E3-18 Maximum Ratings & Electrical Characteristics
| Zener Voltage (Nominal, VZ) | 15 V |
| Zener Voltage Tolerance | ±2% |
| Power Dissipation (Ptot) | 410 mW |
| Power Rating (Datasheet alt.) | 500 mW (per Mouser / Diotec listings) |
| Package | SOD-123 |
| Mounting Type | Surface Mount |
| Number of Pins | 2 |
| Voltage Range (Series) | 2.4 V to 75 V (E24 series) |
| Configuration | Single |
| MSL Level | 1 (per PartGenie listing) |
| RoHS Status | Compliant |
| Packaging | Tape & Reel (E3 = 7" reel, 18 suffix) |
BZT52B15-E3-18 Pin Configuration
| Pin 1 | Cathode — Zener cathode (marked end of SOD-123) |
| Pin 2 | Anode — Zener anode |
Typical Applications
BZT52B15-E3-18 is suitable for 6 applications: 15 V Voltage Reference for ADC/DAC Front-End, Over-Voltage Clamp for MCU I/O Lines, Precision Regulated Supply for Sensor Conditioning, Voltage Reference in Portable / Battery Devices, Protection Switching and Clamping in Test Equipment, Reference for Automotive ECU Sensor Rails.
15 V Voltage Reference for ADC/DAC Front-End
The BZT52B15-E3-18's 15 V nominal Zener voltage with ±2% tolerance provides a stable local reference rail in ADC and DAC front-end circuits. Placed between the analog supply and the reference pin, it suppresses supply ripple and provides a low-impedance node for the converter reference. Its SOD-123 footprint enables placement directly at the IC power pin, minimizing PCB trace-induced noise pickup. Compared with a series resistor + Zener, the 410 mW rating allows up to ~25 mA continuous load while keeping junction temperature within safe margins on standard FR-4 copper.
Recommended
Over-Voltage Clamp for MCU I/O Lines
The BZT52B15-E3-18 serves as a bidirectional clamp when used in back-to-back configuration on MCU GPIO and communication lines exposed to external transients. Its 15 V Zener voltage sits above the 3.3 V or 5 V MCU rail, clamping inductive kickback and ESD-induced over-shoots to a safe level. The 410 mW power rating handles repetitive transients well below thermal limits, and the SOD-123 package places the protection directly at the connector pin for minimum loop inductance. This protects downstream microcontrollers from factory-floor wiring hazards.
Recommended
Precision Regulated Supply for Sensor Conditioning
Industrial sensor signal-conditioning circuits need a stable 15 V excitation rail for strain-gauge bridges, RTD interfaces, and 4-20 mA loop transmitters. The BZT52B15-E3-18 provides a low-cost local 15 V reference derived from a higher switching rail, with ±2% tolerance sufficient for many transducer excitation requirements. Its planar-junction Zener architecture gives stable temperature behavior, and the small SOD-123 footprint permits placement inside the sensor housing itself, reducing field-wiring-induced noise pickup on the bridge output.
Recommended
Voltage Reference in Portable / Battery Devices
In portable and battery-powered devices, the BZT52B15-E3-18 acts as a low-power voltage reference for battery monitoring, charging state indicators, and threshold detection. Its 410 mW power rating is far above the typical µA bias currents required, ensuring negligible self-heating and long battery life. The SOD-1201 surface-mount outline is suitable for handheld device PCBs where board area is constrained, and the ±2% tolerance is adequate for battery fuel-gauge and warning-threshold circuit applications.
Recommended
Protection Switching and Clamping in Test Equipment
Bench-top test and measurement equipment such as digital multimeters, oscilloscope front-ends, and signal generators benefit from over-voltage protection at input terminals. The BZT52B15-E3-18 clamps incoming transient voltages to 15 V, well within the safe operating area of downstream analog front-end ICs. Its 410 mW rating handles the short-duration transients typical of probe scope, while the small SOD-123 package fits directly at the BNC connector footprint for minimum ground-loop inductance.
Recommended
Reference for Automotive ECU Sensor Rails
In automotive ECUs, the BZT52B15-E3-18 (or its AEC-Q101-qualified HE3 variant) generates a local 15 V reference for sensor excitation rails such as throttle position sensors and MAP sensors. The HE3-grade variant (BZT52B15-HE3-18) provides the same 15 V ±2% reference with automotive screening per Vishay's HE3 designation. The SOD-123 package withstands automotive under-hood and cabin temperature profiles, and the planar-junction construction gives long-term stability required for OEM ECU lifetime requirements.
Recommended
Recommended Products Summary
Engineering reference data for BZT52B15-E3-18 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BZT52B15-E3-08 | BZT52B15-HE3-18 | BZT52B16-E3-18 | BZT52B14-E3-18 | BZT52-B15 | BZT52B15-TP | BZT52B15 |
|---|---|---|---|---|---|---|---|---|
| Package | SOD-123 | SOD-123 - same | SOD-123 - same | SOD-123 - same | SOD-123 - same | SOD-123 - same | SOD-123 - same | SOD-123F (SOD-123 flat-lead footprint-compatible) |
| Brand | Vishay | Vishay | Vishay | Vishay | Vishay | Nexperia | MCC | Diotec Semiconductor |
| Nominal Zener Voltage (VZ) | 15 V | 15 V | 15 V | 16 V | 14 V | 15 V | 15 V | 15 V |
| Zener Tolerance | ±2% | ±2% | ±2% | ±2% | ±2% | ±2% | ±2% | ±2% |
| Automotive Grade | No (commercial) | No | Yes (HE3 = AEC-Q101 automotive) | No | No | No | No | No |
| RoHS Compliance | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Same VZ and footprint as E3-08 with higher reel-piece count (vs BZT52B15-E3-08)
- Commercial-grade vs automotive-grade variant in same footprint (vs BZT52B15-HE3-18)
- Cross-brand drop-in via Nexperia B-series die (vs BZT52-B15 (Nexperia))
- Pin-compatible alternative at 16 V for slightly higher reference (vs BZT52B16-E3-18)
Design Notes
Estimated: at 15 V nominal and 25 mA load (typical IZT margin), the BZT52B15-E3-18 dissipates approximately 375 mW, near the 410 mW rating. Above 25 °C ambient, derate linearly per Vishay's power-derating curve. For continuous operation at 410 mW, junction temperature must remain below the maximum rated Tj; ensure 40 mm × 40 mm × 0.022 L footprint pad geometry with thermal vias to inner layers for effective heat spreading. In sealed enclosures, derate further or move to a higher-rated package.
Solder the cathode pad (pin 1) to the larger copper pour — typically a thermal pad connected to the protected net — and minimize trace length from the cathode to the protected node. The SOD-123 outline has a cathode-mark band on one end of the package; orient the part with the band facing the protected IC pin. Avoid routing sensitive analog signal traces beneath the Zener to prevent coupling of switching transients into the signal path. Use a 0402/0603 ceramic decoupling cap on the downstream rail for additional HF noise suppression.
Do not operate the BZT52B15-E3-18 at currents far below the specified IZT — the Zener voltage rises sharply at low currents and the dynamic impedance increases, degrading reference accuracy. Verify VZ at the actual operating current in the datasheet's VZ vs IZT curve. Do not exceed the maximum reverse current or peak forward surge; transient pulses must stay within the non-repetitive surge rating. When using as a precision reference, avoid paralleling multiple Zeners — current hogging leads to thermal runaway on the lowest-VZ device.
Compliance Information
RoHS compliant per Vishay product page and PartGenie listing. REACH compliance status not explicitly stated in verified web data. E3 suffix per Vishay convention indicates lead-free terminal finish. Choose BZT52B15-HE3-18 variant for AEC-Q101 automotive applications.
