Because many of the challenges associated with optocouplers are met and fixed, Skyworks Solutions Si87xx products are termed drop-in upgrades for common optocouplers. The core component of optocouplers is an LED which is negatively affected by age and forward current. This, along with other inherent aspects of optocoupler technology, limits the lifetime of the devices. The Si87xx isolators use only standard CMOS process technology which is very stable over its lifetime and in all environmental conditions. Lifetimes, as measured by MTTF, can be more than 10x better than optocouplers. The internal LED used by optocouplers requires a high forward current in order to keep the signal at a reliable level. In addition, output stages of optocouplers are not optimized for power. The Si87xx does not use an LED; the LED emulator gives the full noise performance while using one half of the forward current. Also, by using a standard CMOS process, the output stage can be optimized and quiescent current is greatly reduced. The physical structure of the optocoupler guarantees that the devices will exhibit large parasitic capacitance. That parasitic capacitance creates an inherent limit on the noise immunity specification. In contrast, the physical properties of the Si87xx products ensure that the parasitic capacitance is very low so that CMTI performance can be increased by 75%. LED switching as performed in optocouplers is slow and leads to large signal propagation delays. The CMOS isolation used in the Si87xx isolators allows for very fast switching.