 I'm John Johnson, Automotive Systems Marketing at ST Microelectronics. Our topic for today is the onboard charger and electric vehicles. We'll discuss some EV charging basics, a block diagram of the onboard charger, and talk about some solutions for OBC offered by ST Microelectronics. So hop in and let's go! The onboard charger serves as a bridge between the battery management unit slash battery and the electrical vehicle service equipment, that is EVSE. In the battery electric vehicle world, EVSE is analogous to a gas pump in the internal combustion engine world. The onboard charger converts the line level electricity from the grid, in AC, into current that is used by the BMU to charge the battery, DC. Before onboard charging is discussed, let's take a quick look at electric vehicle charging stations. As shown in the table, there are three basic levels of chargers for BVE being deployed. Level three chargers are capable of charging a vehicle in less than 30 minutes. While this is certainly slower than filling a tank with petrol or diesel, it helps consumers accept that EV is a viable transportation alternative even for longer trips. And in case there's a mishap, there are service providers that are happy to bring a diesel generator alongside the vehicle in the event of a charging emergency. The SAE and VDE have defined connectors for various use cases for EVSE. Notice the CCS connector provides a plug for the baseline connection, including a pilot signal, etc., and high voltage DC connections. These types of charger, level three, can charge up a vehicle in under 30 minutes. In this case, DC current is supplied directly to the battery slash BMU. For level one and level two EVSE, the AC service supplied to the connector is converted into DC current by the onboard charger. Several factors go into the choice of charger topology employed as well as the components selected for each section of the onboard charger. Let's examine a generic block diagram of the OBC Next. Here is a generic block diagram of the OBC with major blocks identified. There is more to an OBC than the DC-DC converter, as you can see. After the line voltage enters the vehicle, it is usually filtered, and then it connects to a power factor correction block. PFC not only ensures that the OBC operates at peak efficiency from an energy usage perspective, but it also is used to reduce emissions by mitigating the nature of the load presented to the grid by the vehicle. A bulk of the conversion from AC to high voltage DC is performed by the DC-DC converter block. Of course, what all of this comes in the need to connect, monitor, control, and manage power. Specific operational parameters for each vehicle system largely determine which transistors in switch technology is most suitable. These use cases, for example onboard charger, have requirements that dictate how much power needs to be switched, as well as transistor switching speeds. As shown in the diagram, the characteristics of silicon carbide, MOSFETs, and gallium nitrite are suitable for onboard charger applications. This chart illustrates the operational domains of automotive rectifiers and diode components. As discussed, the input section PFC and DC-DC converter perform the heavy lifting of the energy conversion in an onboard charger. Both schemes are employed depending on the amount of efficiency sought and the amount of power that needs to be converted by the OBC. Single or polyphase AC power is applied to the input. PFC can either be very basic or employ sophisticated interleave schemes. DC-DC conversion also incorporates many different topologies as well. Shown above is a partial list of the power devices commonly found in OBC designs. Silicon also plays an important role in ensuring that the components deliver efficient, reliable performance over the service life of the vehicle. The bottom line is that ST Microelectronics provides solutions to difficult onboard charging design challenges. So give your local sales team a call or contact us at www.st.com. I'm John Johnson for ST Microelectronics.