Overview
- Apple disclosed Tuesday that engineers routed a flexible graphite pipe through the iPhone Duo’s hinge to move heat between the two halves and boost the surface area available for cooling when the phone is folded.
- The A20 Pro used in the Duo adopts wafer-level multichip module packaging with DRAM placed beside the processor rather than stacked, a change Apple says spreads heat while keeping fast memory links.
- Apple enlarged the vapor chamber to roughly three times the prior surface area, added more de-ionized water, and redesigned the chassis to give the chamber a more direct thermal path to key components.
- Engineers created a ‘metal over foam’ thermal bridge to couple the SoC to the vapor chamber while meeting mechanical needs, and the Duo variant of A20 Pro adds a second display engine and under-display FaceTime camera support.
- Apple frames these coordinated hardware changes as engineered mitigations to folded-state heat, but the company and reviewers note that real-world sustained performance and long-term hinge durability must be validated in consumer use.