“Cars are becoming increasingly digital, defined by their software as much as their engines and transmissions.” —NYT
In a recent article on how Tesla is running circles around traditional automakers, The New York Times suggested that because they were really an agile tech company, they had an extreme advantage.
Agility is key in the EV sector, where change is coming fast and furious. On-board and off-board charging systems are consistently requiring increased power and higher efficiency. In order to enable this architectures need to run faster, be more accurate, and have less latency—all while maintaining the same or smaller form factors.
And it’s not just happening in EVs—the same demands are being seen in industrial, telecom, and consumer electronics.
Traditional, Hall-based sensors can no longer provide the need for low power consumption, high sensitivity and accuracy, at an affordable cost, meaning new technologies are needed. For these benefits, AMR and GMR sensors are quickly giving way to TMR sensors.
TMR excels as a current sensor, since a TMR sensor’s resistance changes according to the external magnetic field. When it’s combined with state-of-the-art CMOS circuitry, these sensors can be used as high-SNR sensors, delivering excellent linearity and thermal performance— as a contact or contactless current sensor.
Power-factor correction increases the power factor of a load, improving efficiency for the distribution system to which it is attached. In an electric power system, a load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. With the increased demand that EVs will have on our energy infrastructure more emphasis is being placed on improving PFC efficiency.
New PFC architectures combined with higher efficiency GaN devices are enabling new levels of efficiency and power density. The totem-pole PFC is the architecture of choice for this application and there are more and more controllers being released that support this. This new architecture is changing the game for the EV on-board and off-board chargers, computing, and data centers.
According to Crocus, developer of most advanced magnetic TMR sensor technology solutions, an XtremeSense™ TMR sensor is the ideal solution for isolated current sensing in these applications. The Crocus TMR sensor provides high SNR and clean signal to the controller, low power loss and 1-MHz bandwidth with low latency and fast output response time (300 ns) for measurements. The TMR sensor also features programmable overcurrent detection and high-voltage isolation to ensure safety.
Bottom line: Engineers using a Hall-based sensor will be pleasantly surprised by the significant advantages they will gain in system on accuracy, bandwidth, latency, and overall efficiency.