The emerging trend of vehicles going electrical and adopting ever-more automotive electronics has not only brought new growth opportunities for the entire automotive industry, but also enabled semiconductor makers to use more of their solutions to solve the resulting technical problems. Texas Instruments (TI), for instance, has recently launched two solid-state relay chips to improve power isolation in EVs.
According to Priya Thanigai, manager of power switches at TI, traditional mechanical relays could work well in isolating power current in oil-fueled vehicles as there were fewer components operating under high-voltage power current scenarios. But higher-spec isolation solutions are now badly needed to secure EV driving safety, because electrical batteries, power management solutions, charging and many other modules inside the vehicles all have to use high-voltage currents, Thanigai said.
Accordingly, power isolation is extremely important in EVs, and will be even more so, as the EV industry transitions from 400V batteries to 800V ones. Thanigai noted TI's solid-state relays, dubbed TPS13050-Q1 and TPS12140-Q1, are able to offer longer operating life and higher isolation capability than mechanical or photo relays.
Thanigai stressed that both mechanical and photo relays, now still widely adopted in vehicles, cannot meet product life and switching speed requirements under high voltage current scenarios of EVs and will thus seriously affect the operations of the vehicles and increase safety risk. In this regard, TI's semiconductor solid-state relays can fill the specification gap.
Thanigai also noted that old relay solutions are generally large in size and should be paired with a lot of peripheral components that can hardly be integrated. In the future, it will be difficult to fit so many relays into a new module, as the number of electronic components in EV will increase significantly, and therefore only smaller semiconductor solid-state relays can enable lighter modules and more efficient vehicle operation, while also able to monitor internal current switching and the functional conditions of various electronic components.
Thanigai acknowledged that the ratio of customers actually incorporating semiconductor relays is not high for the moment, but they are aware that existing relay products cannot solve high-voltage isolation needs for EVs. As such, TI believes that its solid-state relay products can well enter the EV market in the future, in addition to industrial control and other infrastructure applications.