Original Part
Alternative Part
1. PS2561A-1-A Substitution Conclusion
Based on a comprehensive evaluation, the PS2561A-1-A can serve as a direct replacement for the original PS2501A-1-A. The two devices are identical in their core electrical parameters and mechanical package: both are single-channel, feature a 5000Vrms isolation voltage, the same current transfer ratio (CTR) range (50% to 400% at 5mA), identical output capability (70V, 30mA), and share the same 4-DIP package. The only discernible difference is a shift in the typical forward voltage (Vf) from 1.17V to 1.2V. This minor variation (approximately 0.03V) has a negligible impact on the calculated LED drive current in practical circuit design. It typically falls well within the design margin and will not affect the optocoupler's normal turn-on or functional performance.
2. PS2501A-1-M-A Substitution Conclusion
A comprehensive assessment indicates that the PS2501A-1-M-A can directly substitute the original PS2501A-1-A. This model is a derivative within the same product family and matches the original in all key parameters, including channel count, isolation voltage, current transfer ratio (CTR), switching speed, output specifications, and package. The primary difference, once again, lies solely in the typical forward voltage (Vf), which has been adjusted from 1.17V to 1.2V. Under the same input-side current-limiting resistor condition, this change results in an extremely slight decrease in the current flowing through the input LED. However, given the broad and consistent CTR range of both devices, this discrepancy will not produce any observable effect on the output logic levels or drive capability. In the vast majority of applications, a pin-to-pin, seamless replacement is fully achievable.
Analysis ID: E5F0-F724000
Based on part parameters and for reference only. Not to be used for procurement or production.
SkyChip © 2026, Email: sales@skychip.com