Automotive eCall power supply reference design with low intermediate voltage

This reference design includes a complete power management solution for a standalone emergency call (eCall) system in an automotive environment. The circuit is supplied directly from the car battery rail. It also manages a backup battery to power the eCall system while the car battery rail is not available. It includes power path management which routes the available power rail directly to four DC/DC converters which are supplying the required functional blocks of the eCall system. The solution is optimized to operate at maximum efficiency while powered from the backup battery.

Features

• Complete power solution for an automotive eCall system
• Operating input voltage range up to 40V
• Provides supply voltage for all required eCall functional blocks
• Up to 87% total efficiency while operating at backup power
• Up to 90% total efficiency in standby at backup power
• All DC/DC converters used can operate at switching frequencies above 2MHz

Parts Include:

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TAS5421-Q1  22-W Mono Automotive Digital Audio Amplifier With Load Dump and I2C Diagnostics 
TL331-Q1  Automotive Catalog Single Differential Comparator 
TPS61175-Q1  3-A High-Voltage Automotive Boost Converter with Programmable Switching Frequency
TPS62290-Q1  Automotive Catalog 2.25MHz 1A Step-Down Converter in 2x2mm SON Package 
TPS63020-Q1  High Efficiency Automotive Single Inductor Buck-Boost Converter with 4A Switch 

Learn more by downloading the reference design below