Apple is working on an updated version of its C1 modem, which first appeared in the iPhone 16e. The current C1 modem uses different manufacturing processes for its components: 4/5nm for the baseband, 7nm for the transceivers, and 55nm for the power management integrated circuit (PMIC).
The refreshed C1 modem is planned for mass production next year. Apple hopes to improve power consumption and transmission speed with this new version. It will also add support for mmWave technology, including transceivers and front-end components built on a 28nm process.
Adding mmWave support isn’t technically difficult, but achieving stable performance with low power consumption remains a challenge for Apple. This is likely why the current C1 modem doesn’t have mmWave support, which limits users’ access to ultra-fast 5G speeds in certain locations.
Unlike processors and GPUs, baseband chips don’t usually use the newest manufacturing processes. This is because newer processes don’t greatly improve baseband transmission speeds. Also, although newer processes can improve power efficiency, the baseband isn’t the biggest power consumer in a phone’s wireless system.
Because of these factors, Apple probably won’t use a 3nm process for its baseband next year. Instead, the company seems to be focusing on improving the overall system rather than using the newest manufacturing process for each part.