Renesas moves to chiplets for automotive processors

The company revealed this when announcing its 5th generation ‘R-Car’ product range, the first of which will be sampling late next year for cars shipping in 2027.

Chiplets are simply die to be used inside multi-die packages. They increase product yield by moving from one large die to two or more smaller dies, and the chiplets – perhaps an AI accelerator in the Renesas case – can be re-used inside other chiplet-based ICs.

The technology also allows die made on differently-optimised processes to be combined – memory and processor logic, for example, and allows die from different manufacturers to be combined – at a presentation, Renesas would not rule out using AI accelerator die from third-parties in its R-Car gen 5 products.

Its fifth gen R-Car products will be Arm-based and, it said, the range of processing capabilities available from these ICs will be wider than is being offered in fourth generation ICs, which are ramping up in production now.

To make the performance range wider at the top end, gen5 R-Car SoCs (microprocessors in old language) will get AI performance dramatically higher than in 4th generation SoCs, for example, said Renesas.

At the low end, not using chiplets, the company is proposing R-Car ‘Next MCU’ microcontrollers for simple control tasks, plus something it is calling ‘Crossover MCU’ to bridge the gap between the performance of those compatible MCUs and the fifth-generation R-Car SoCs.

The “crossover MCU series [will be] designed to deliver the performance required for domain and zone electronic control units in next-generation architectures in automobiles”, according to the company. “As part of its roadmap, Renesas plans to offer a virtual software development environment that aligns with the auto industry’s move toward ‘shift left’ approach. These software tools will allow customers to design and test software earlier in the development process, even before hardware arrives.”

How deep software and tool-compatible will go between Gen 5 SoC, Crossover MCU and Next MCU has not been disclosed. The first tools are scheduled to appear in 1Q 2024.