MMBT5551_R1_00101
Panjit International Inc.
Needs validationmedium risk
MMBT5551 can be a functional NPN option where pinout and bias are rechecked.
Best Alternatives to BC817
BC817 is a 45V, 500mA NPN transistor in SOT-23. Candidate substitutes need pinout and thermal review before use.
AI replacement insight
Electrical riskmedium
gain, power, and bias may differ
Package riskmedium
SOT-23 matches but pinout is not shown
Firmware risklow
discrete BJT has no firmware
Sourcing riskmedium
lifecycle fields are limited
Can it be replaced directly?
No confirmed pin-compatible replacement is proven from the provided fields.
Best replacement path
Review FMMT495 first for higher V/I, then verify pinout and power derating.
Main risk
Pinout is missing and some candidates change power or gain behavior.
Recommended alternatives
1Alternative comparison matrix
| Feature / factor | BC817 | FMMT495 | MMBT5551_R1_00101 | Alt 3 | Compatibility / risk |
|---|---|---|---|---|---|
| Package | SOT-23, 3pin | SOT-23, 3pin | SOT-23, 3pin | SOT-23, 3pin — same package count; MMBT5551_R1_00101: same package count | |
| Pinout | BC817 pinout | not provided | not provided | not provided — no pin map evidence; MMBT5551_R1_00101: no pin map evidence | |
| Voltage | 45V VCEO | 150V VCEO | 160V VCEO | 150V VCEO / 160V VCEO — meets 1.1x rule; MMBT5551_R1_00101: meets 1.1x rule | |
| Current | 500mA | 1A | 600mA | 1A / 600mA — higher IC; MMBT5551_R1_00101: slightly higher IC | |
| Power | 300mW | 250mW | 250mW | 250mW — derating needed; MMBT5551_R1_00101: thermal review |
Application & sourcing insights
Questions & answers
From the provided data, FMMT495 is the strongest candidate but still needs pinout and power review.