On October 13th, according to a report from technology media PCMag, they conducted an interview with two senior executives from Apple yesterday (October 12th), revealing for the first time the hinge cooling solution for Apple's first foldable phone, iPhone.
Dan Murray, Vice President of Chip Engineering at Apple Inc. ( Dan Murray ), and Barnavesh Balabadi, Senior Manager of Apple's Thermal Design Product Team ( Banafsheh Barabadi ), disclosed in detail Apple's custom thermal solutions during an interview with the media. As a result, in iPhone 18, Pro , iPhone 18, Pro , and iPhone Duo , they were able to maximize the continuous performance output of the A20 Pro chips.

In terms of packaging, the chip adopts a wafer-level multi-chip module (WMCM) packaging method, moving DRAM from above the processor to the side. As cited in a blog post by IT, Apple describes this design as establishing a direct thermal path from the chip to the heat spreader, eliminating the thermal dissipation bottleneck present in previous packaging stack (POP) solutions.

In iPhone, Pro and Pro Max, the surface area of the heat spreader is 3 times that of iPhone and Pro, and it contains more deionized water inside. This heat spreader also serves as a mechanical framework; the battery and logic board are directly mounted on it, and 80% recycled stainless steel is used in its construction.
Apple also uses nanotwinned copper metal plates on the back of the screen, along with a layer of highly thermally conductive graphite. These two materials work together to improve the horizontal heat dissipation of the display, reduce hot spots, and at the same time meet the mechanical strength requirements of the display.
iPhone Duo uses a thinner heat spreader than iPhone by 18 Pro, and it is suspended in the middle of the fuselage. Since the thickness of the fuselage doubles when folded, Apple connects the cooling structures on both sides through flexible graphite tubes inside the hinge.
Flexible graphite tubes are a type of flexible thermal conductive component made of graphite material, which can be bent and arranged in limited spaces. They transfer heat from hot areas to other parts of the device, and are commonly used for heat dissipation in electronic devices with compact internal spaces such as smartphones and laptops.
Apple stated that the new cooling system supports tasks such as gaming, video recording, and device-side AI. The continuous GPU performance has increased by 35% compared to iPhone from 2017; the CPU performance has improved by 20%, and the graphics performance has increased by 40%.












