SoC

Josh:
00:00
The first cell phone I ever owned was an LG track phone.

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This was a small, by today's standards, flip phone.

00:08
It had a screen on the inside when you flipped it open, and a small screen on the outside.

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This was around the time when you had to pay for every individual text message that you sent, so I didn't send any.

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Funny enough, I actually didn't even want a cell phone at the time.

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I tried to wait as long as I could to not have one.

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But since I had just got my learner's permit to start driving, my parents thought it would be a good idea for me to have one.

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There was nothing special about it. It made calls, and I could listen to voicemails.

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There was no data, so I couldn't browse the web.

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Not that you'd want to, because the interface was terrible, and the mobile browsers at the time were miserable to navigate with.

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The LG track phone was a phone with a chip that could do some computation.

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Today's phones with their system on a chip, also known as a sock,

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There's nothing but it's fine, there's nothing but a mouse in it.

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It's fine but I know if it's fine.

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So something to see with a phone 취 physicists at the time,

01:00
is a computer that just so happens to make phone calls from ram to gpu to cpus to a single chip

01:07
on this episode of in the shell the wrong thing to do is just go out and buy a computer and then

01:14
learn about it you'll learn but you'll learn a lot of things that maybe you didn't want to learn

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a computer that you buy today will likely be obsolete six months from now and there's not

01:25
a dang thing that you can do about it my name is josh and i'm able to keep this podcast independent

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and advertisement free because of support from listeners like you if you are finding value in

01:39
what i'm doing here consider becoming a paid supporter at members.sideofburritos.com and as

01:46
a thank you members get early access to new videos ad free versions of everything bonus content and

01:52
access to a live monthly q a thanks for considering now let's get back to the show if you

02:00
crack open a modern smartphone, you won't find a big motherboard with separate chips for the

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processor, graphics, and memory like in a PC. Instead, there's usually one main chip about the

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size of a fingernail. This is the System on Chip, SOC, an integrated circuit that packs most of a

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device's critical components, CPU, GPU, memory controllers, wireless modems, onto a single piece

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of silicon. This high level of integration minimizes the need for multiple discrete components,

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which in turn enhances power efficiency and simplifies device design. Because SOCs combine

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so many things together, they allow mobile devices to be incredibly compact. In a desktop computer,

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the CPU, GPU, RAM, and other components sit separately on a large board. But in a phone or tablet,

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the SOC approach crams that computing power into a single chipset.

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The result is that even a slim phone can do complex computing tasks since its system lives

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on one efficient chip.

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It wasn't always possible to put an entire system on one chip.

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In the early days of electronics and mobile phones, a handset needed numerous chips working

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together, one for the CPU, others for memory, a separate baseband modem for calls, another

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for the radio transceiver.

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If you remember old mobile phones, or even early smartphones, they were relatively bulky.

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Part of that bulk was due to having a circuit board crowded with many specialized chips handling

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different tasks.

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By the late 1990s and early 2000s, the industry was pushing hard to miniaturize and combine

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these components.

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The impact of this evolution was huge.

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Integrating formerly discrete components into a single SOC brought shorter interconnections

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and system-level optimizations that make the whole device

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get theõe and secure.

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So I don't think it's just a long time on the server.

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run more efficiently. That means phones could keep getting smaller and thinner, even though I think

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they are thin enough already, since one tightly integrated chip replaced many larger ones.

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It also laid the groundwork for today's wearables and IoT gadgets. Efficiency gains also come from

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optimization. The chip's designers can coordinate how the CPU, GPU, and other units work together,

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scheduling tasks and managing clock speeds in a tightly integrated way. The result is often

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higher overall performance since signals stay on chip. There's also economic and reliability perks

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as well. Fewer separate parts on a circuit board means fewer points of failure. A single chip has

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many internal connections, but far fewer pins and soldered joints externally compared to a multi-chip

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solution. This compact simplicity can make devices more robust and cheaper to produce at scale.

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Of course, the trade-off

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is that if something does go wrong inside the sock, you can't just replace one component.

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The entire chip would need replacing. So as far as repairability goes, that's a downside.

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Not that many of us would be soldering chips at that level. Now as far as socks go, each big

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manufacturer has their own. Apple designs its own sock for iPhones and iPads, known as the A-Series

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Chips. These chips integrate a multi-core 64-bit CPU, Apple's custom GPU, and specialized neural

05:24
oh

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engines and image processors on one silicone die. Apple even embeds a secure Enclave coprocessor

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in its socks, a dedicated security subsystem isolated from the main CPU, to handle sensitive

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data like Touch ID, Face ID, and biometrics. By crafting the entire sock in-house, Apple has

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been able to optimize iOS to run extremely efficiently on that hardware.

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much like they later did with the M chips in Macs. Now moving to Android, Qualcomm's Snapdragon line

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is ubiquitous in Android smartphones. A Snapdragon is a full system-on chip that typically includes

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multiple ARM-based CPU cores, an Arduino GPU, and a built-in cellular modem for 4G and 5G

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connectivity all on the same chip. Snapdragons also have signal processors for audio and video,

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GPS receivers, AI acceleration engines, and more depending on the model. This means a phone from

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Samsung, OnePlus, or Xiaomi that uses a Snapdragon chip can rely on that one piece of silicon to

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handle everything from running apps to connecting to calls over a 5G network. And sticking with Android,

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even Google has their Tensor chip, which they first introduced in the Pixel 6 phone. Google Tensor was

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co-developed with Samsung and is a custom SOC tailored for Android.

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for Google's needs.

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It combines standard ARM CPU cores and the Mali GPU

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with Google's own AI and machine learning silicon.

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Besides some of the benefits I mentioned earlier,

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moving to an all-in-one chip

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can also bring security advantages.

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One benefit is that with fewer separate components

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and exposed connections,

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there are fewer attack surfaces for hardware hacks.

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In a traditional PC, data travels over external buses

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between the CPU, RAM, and peripherals,

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which could potentially be intercepted or tampered with.

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In a single chip system,

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much of that communication is internal to the silicon.

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Modern SOCKs also come

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with hardware security features built in.

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Because the manufacturer controls the whole chip design,

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they can embed dedicated security subsystems.

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There's Apple's Secure Enclave,

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which is a secure coprocessor integrated

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into the SOCK of iPhones and Macs.

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to keep sensitive data isolated. Most ARM-based SOCs, which includes the Snapdragon and Tensor,

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implement ARM Trust Zone technology, which creates a secure execution environment on the

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SOC itself. It means the chip can run a trusted OS in parallel with the main OS, handling things

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like cryptographic operations or authentication in a walled-off area of the processor.

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In addition, SOCs often support Secure Boot, which ensures the device only runs trusted

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signed software and have on-chip cryptographic engines for speedy encryption and decryption

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that never expose keys to the outside. I think SOCs are one of the most important

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advancements when it comes to hardware privacy and security, and nearly all of us hold one

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in our hand every day and rarely give it a second thought.

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In the Shell is written, researched, and recorded by me.

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me.

09:00
the podcaster on a chip. If you're listening in an app that lets you rate shows,

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please take a minute to rate this one. I would truly appreciate it.

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And when you travel, always remember to bring extra socks.

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That's it. Take care, and I'll see you next time.