Infineon’s New ASIL D Compliant PMIC Hits the Road
Infineon has released a high-reliability power-management IC (PMIC), the TLF35585, designed to meet the stringent safety and performance demands of automotive systems.
TLF35585QU in TQFP-48 package.
The TLF35585 is Infineon's latest addition to its broader Optireg PMIC portfolio, which is optimized for highly efficient voltage regulation. In addition to innovations in efficiency, devices in the family also feature functional safety compliance for automotive systems. TLF35585 can work with Infineon’s Aurix family of microcontrollers (among others) to regulate power in a harsh automotive environment.
Key Features for Maximum Efficiency
The TLF35585 PMIC (datasheet linked) features a boost buck pre-regulator powering the post-regulator rails responsible for supplying the microcontroller, communication circuits, and a stable voltage reference. Additionally, it includes two trackers that adjust based on the voltage reference to provide power to offboard sensors. The TLF35585 includes a configurable window watchdog (time-based monitoring), a functional watchdog, error pin monitoring, and voltage supervision. The TLF35585 also supports 16-bit SPI communication, interrupt handling, and reset functionality for easy interfacing with Aurix microcontrollers.
Serial Peripheral Interface (SPI) is a communication protocol used to connect microcontrollers to peripheral devices. It is often used for applications that need quick data exchanges. The TLF35585 meets (ISO 26262) ASIL-D, the highest safety standard for automotive systems, ensuring it can handle critical functions like braking and powertrain control with minimal risk of failure.
The TLF35585 features an SPI interface for communication with an MCU.
Additionally, it operates at temperatures up to 175°C, making it suitable for high-heat areas in vehicles like powertrains and battery systems. It includes a low-drop post regulator providing 3.3 V/600 mA for the microcontroller, a 5.0 V/200 mA post regulator for the communication supply, and a 5.0 V/150 mA voltage reference with ±1% accuracy for the ADC supply.
Package Sizes
The TLF35585 comes in VQFN-48 and TQFP-48 packages, both offering high thermal performance. These packages are AEC-Q100 qualified (Grade 0), ensuring reliability for automotive applications. Specifically, TLF35585QUS02 and TLF35585QUS01 are offered in TQFP, while TLF35585QVS01 is offered in the VQFN package.
While the automotive PMIC market is competitive, with many manufacturers offering comparable ASIL D-compliant PMICs (NXP's FS04 PMIC, for example), the TLF35585 stands out in several ways. First, the TLF35585 is AEC-Q100 Grade 0 qualified for the harshest automotive environments, while the FS04 is Grade 1 qualified. Another way the TLF35585 differentiates itself is its high input voltage range from 3 V to 40 V.
With these features, the new power supply solutions meet the functional safety requirements of harsh automotive environments, making them potentially useful in powertrain, chassis, domain control, and transmission areas. The PMICs' utility may extend beyond automotive applications with its flexible state machine, standby regulator, and wakeup concept with a timer.
