MMSZ5245B
Fairchild Semiconductor
Needs validationlow risk
MMSZ5245B is a potential pin-compatible alternative with matching 15V Zener voltage and 500mW power rating in an SOD-123 package.
Best Alternatives to BZT52B15
BZT52B15 is a 15V, 500mW Zener diode in a common SOD-123 package. For replacement, MMSZ5245B is a strong pin-compatible candidate available from multiple manufacturers.
AI replacement insight
Electrical risklow
MMSZ5245B has matching or better electrical specs.
Package risklow
SOD-123 is standard, but verify no 'F' or other variants are used.
Sourcing risklow
Strong alternatives are available from multiple major manufacturers.
Can it be replaced directly?
Direct replacement for BZT52B15 should use only Datasheet verified or Strong match candidates; many approved options still require engineering review.
Best replacement path
Use MMSZ5245B from a reputable manufacturer like onsemi or Diodes Inc. after verifying the 500mW power rating from its datasheet.
Main risk
The primary risk is accidentally sourcing a version with a lower power rating (e.g., 350mW) or a slightly different package footprint (e.g., SOD-123F).
Recommended alternatives
2Alternative comparison matrix
| Feature / factor | BZT52B15 | MMSZ5245B | BZT52C16 | Alt 3 | Compatibility / risk |
|---|---|---|---|---|---|
| Package | SOD-123 | SOD-123 | - | SOD-123 — Form and fit match. | |
| Voltage | 15V | 15V | - | 16V — Zener voltage is higher, which will change regulation point. | |
| Power | 500mW | 500mW | - | 500mW — Matches target power rating. | |
| Zener Impedance | 30Ω | 13-16Ω | - | 40Ω — Higher impedance will result in poorer voltage regulation. | |
| Current | 100nA | 100nA @ 11V | - | 100nA @ 11V — Reverse leakage current matches. |
Application & sourcing insights
Questions & answers
Verified drop-in options for BZT52B15 are limited in the current batch. Review candidates marked Strong match or Datasheet verified, and validate package, pinout, and electrical limits before committing a BOM change.