When looking at the typical automotive infotainment system design, what is the most difficult design goal to achieve? When I look at how much functionality is crammed into such a small dashboard (core processor and display interfacing with all the different peripherals and power management for all of this), I immediately think of board space (and the associated thermal issues that arise) as being paramount. Without a doubt, reliability and quality are first priorities, but once these are taken care of by each component vendor, then solution size is next up on the list of issues to solve.
While solution size is theoretically easy to solve—just increase the switching frequency to make the passive components smaller—the thermal implications of a small size must not be forgotten. A power supply has significant power dissipation. As the switching frequency increases, this dissipation also increases as several of the losses in a power supply increase with increasing frequency. Therefore, more than a high switching frequency is needed for a reliable and small solution. A good power supply IC design, with a focus on integration and overall solution size as well as thermal capability, is required.
Enter the 3-A TPS62130A-Q1 and its little brother, the 1-A TPS62150A-Q1. Being pin to pin compatible in a small 3 mm x 3 mm QFN package, each device operates with a PWM mode switching frequency of 2.5 MHz. This is well above the AM radio band and above the level that affects many of the sensitive circuits in a car. This high switching frequency enables a solution size under 100 mm2, using inductors as small as 1 µH. Additionally, efficiency was also a key care about in this IC design and over 90% is achieved. Finally, the QFN package is excellent at removing heat, keeping the device and the total solution very cool.
Needless to say, the ‘-Q1’ indicates an automotive device, which in this case is AEC-Q100 qualified up to a 125°C junction temperature. What a small and efficient fit for automotive infotainment applications!
What do you think is the most difficult design goal to achieve in an infotainment system? Leave me a comment and let me know!
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