Before revision: Hybrid integrated circuits (HICs) are somewhat similar to SiPs, however they tend to handle analog URL whereas SiPs usually handle digital URL because of this HICs use older or less advanced technology (tend to use single layer circuit boards or substrates, not use die stacking, do not use flip chip or BGA for connecting components or dies, use only wire bonding for connecting dies or Small outline integrated circuit packages, use Dual in-line packages, or Single in-line packages for interfacing outside the Hybrid IC instead of BGA, etc.).
After revision: All of the components in the apple S1 SIP have digital interfaces such as amplifiers, the STM32 microcontroller, gyroscopes, MEMS microphones, power management ICs, NFC chips which can be seen by looking at their datasheets or datasheets of similar products from the same manufacturersHybrid integrated circuits (HICs) are somewhat similar to SiPs, however they tend to handle analog URL whereas SiPs usually handle digital URL because of this HICs use older or less advanced technology (tend to use single layer circuit boards or substrates, not use die stacking, do not use flip chip or BGA for connecting components or dies, use only wire bonding for connecting dies or Small outline integrated circuit packages, use Dual in-line packages, or Single in-line packages for interfacing outside the Hybrid IC instead of BGA, etc.).