2. HCPL‑4562 Substitution Conclusion Direct substitution of the Toshiba 6N136F with the Broadcom HCPL‑4562 is less feasible and requires circuit evaluation and modification. Although the package is compatible and the isolation voltage (3750 Vrms) is higher, several key parameter differences present significant challenges: first, the CTR (current transfer ratio) range is unspecified, introducing uncertainty in circuit gain and potentially affecting signal‑transfer reliability; second, switching time parameters are not provided, leaving the speed performance unknown and posing a performance risk; finally, the maximum input forward current (12 mA) is notably lower than the original part’s 25 mA. If the original design’s drive current is retained, it could overload and damage the optocoupler—the input‑side current‑limiting resistor must be recalculated and adjusted. This part is suitable only for applications where higher isolation voltage is critical and where the risks of parameter uncertainty and driver‑circuit redesign are acceptable.