Today, almost every new car is equipped with advanced driver assistance systems (ADAS), and the automotive industry is striving for even higher automation. Such safety-critical systems require a dependable and intelligent board net architecture and, in combination with more comfort functionalities, lead to an increasing number of loads. The E/E-architecture therefore requires reliable and intelligent solutions that protect sensitive loads from overcurrent events and ensure fast fault isolation towards the power distribution system.
To address these needs, Infineon Technologies introduces the new automotive smart high-side power switch portfolio PROFET Load Guard 12V. The combination of an adjustable overcurrent limitation and the capacitive load switching (CLS) mode provides a flexible response to the diverse requirements of modern secondary power distribution and provides protection mechanisms for safety-critical ADAS integration.
The new PROFET Load Guard 12V dual- and single-channel devices offer a wide current limitation range between 0.3 and 8.7 A, depending on the RDS(ON). This feature allows the protection level to be set according to the system requirements without microcontroller involvement. It avoids peak currents that endanger loads and provides fast fault isolation to the power distribution side in the event of overload conditions due to failures in loads, e.g. in the sensor fusion box. Loads with high capacitive share, such as ADAS or display modules, can also be quickly switched on using the devices’ capacitive load switching (CLS) mode.
The CLS mode allows to charge several millifarads while remaining within the safe operating area (SOA) of the smart high-side power switches, increasing the overall system robustness. Furthermore, providing a Safety-Application-Note, the PRO SIL™ ISO26262-ready devices simplify the use in functional-safety related applications. In addition, the best-in-class low current sense accuracy enables accurate module diagnostics and monitoring.
The PROFET Load Guard 12V family’s wide operating voltage range from 3 V (cranking: 2.7 V) to 28 V, combined with the adjustable overcurrent limitation and the CLS mode, provides maximum load flexibility. If load or system requirements change, such as variant handling, the analog overcurrent limit threshold can be easily adapted to the new conditions. This is accomplished by simply changing the resistor connected to the OCT pin. In addition to flexibility, this feature also allows for hardware-based wire protection for time-independent loads. The CLS mode further expands the load potential and responds to the increasing number of capacitive loads such as modules.
Rated at 2-3 A, the family consists of two 90 mΩ and two 50 mΩ devices, both available as single- and dual-channel automotive smart high-side power switches. The proven PG-TS-DSO-14 package provides high compatibility with other SMART7 devices such as the PROFET +2 12V. Loads with high capacitive share can be easily addressed via the integrated CLS mode, allowing large capacitors to be rapidly charged within the safe operating area (SOA) of the PROFET Load Guard 12V. The best-in-class high current sense accuracy tolerance (kILIS) in low current ranges enables the highly accurate current sensing.
To support the design-in process of PROFET Load Guard 12V devices, the family is integrated into the PROFET Guard Tool, which is available in the Infineon Developer Center. This tool supports the evaluation of the system protection capability of PROFET Load Guard 12V devices with a given wire and load profile. It also calculates the correct resistor value for the adjustable overcurrent limitation.