Original Part
Bipolar (BJT) Transistor NPN 25 V 50 mA 50MHz 300 mW Surface Mount SOT-23-3 (TO-236)
Alternative Part
Bipolar (BJT) Transistor NPN 25 V 50 mA 50MHz 350 mW Surface Mount SOT-23
Substitution Feasibility Conclusion
The CMPT5089 TR PBFREE can serve as a viable substitute for the SMMBT5089LT1G, as their core electrical parameters—including voltage, current, gain, and frequency—are fully aligned. The CMPT5089 offers improved or wider specifications in terms of power dissipation and low-temperature operating range, which generally enhances its suitability for demanding applications. However, any substitution should involve an assessment of whether the associated cost increase is acceptable, and verification that the application's thermal management and ambient temperature requirements are compatible with the enhanced specifications of the alternative part.
Comparison Points
1. Maximum Power: The CMPT5089 is rated for 350 mW versus 300 mW for the SMMBT5089. The higher power-handling capability of the CMPT5089 provides greater thermal headroom in higher-power applications. However, it is essential to confirm that the original design (e.g., PCB thermal layout) can accommodate this increase to avoid potential over-design.
2. Operating Temperature Range: The CMPT5089 supports a range of -65°C to 150°C, which is wider than the -55°C to 150°C range of the SMMBT5089. This indicates that the CMPT5089 is suitable for more extreme low-temperature environments (e.g., aerospace or automotive electronics). If the application's minimum temperature does not fall below -55°C, this difference has no practical impact.
3. Price: The CMPT5089 carries a higher unit cost ($0.70000 vs. $0.40000), which may increase overall cost in volume applications. A cost-benefit analysis should be performed when considering the substitution.
Analysis ID: CFED-02AE000
Based on part parameters and for reference only. Not to be used for procurement or production.
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