OptoMOS’s are a great alternative to the earlier isolated switching options. OptoMOS's are compact, generate no noise and have a clean switching without any chatter. However, OptoMOS’s tend to have a limited lifetime due to the associated aging of the LEDs over use. This means that one needs to bias the forward LED with higher current to compensate for LED lifetime aging. This factor further increases if the usage is at higher temperatures. As depicted in Figure 1-2, light output within an optically-isolated switch reduces by about 10% across devices after just one year of use. This leads to higher power consumption long-term as the initial bias current needs to be higher to compensate for this degradation.

Figure 1-2 LED Deration Over Lifetime Usage (Representational)

TI’s Isolated switches (ISOMOS) use Silicon Dioxide (SiO₂)-based isolation with electrical signaling across the barrier for communication, as shown in Figure 1-3. As all the circuits are realized in silicon, there is no associated aging on the circuits. There is no need to compensate for lifetime usage of the device, as one must with traditional LED-based OptoMOS’s. This enables easier and cooler designs that work reliably over system lifetime.

Figure 1-3 Cross Section of an Opto-Emulator

Isolated switches are commonly used in various applications across industrial and automotive sectors where one can safely connect/disconnect a part of the circuit based on a control signal. Some of the key applications for ISOM8610 in different end-equipments like Factory automation, Building automation, and Intrusion alarms are discussed in the following section.