The Big Automotive Semiconductor Problem
If you want to see the video, it is below:
Some of the biggest shortages in the semiconductor industry today are in the trailing edge semiconductor world. 40% of the demand for this trailing edge technology are from the automotive industry.
Recently, I have been thinking about the ways integrated circuits subsume the functions of discrete systems. Mobile phone SOCs integrate a substantial amount of function right onto the chip. Why hasn’t that been the case for the car? I don’t have an answer. But I wonder if it has to do with the fact that many of the control units within the car are sensor-based. MEMS sensors are really cheap and work better than the old ones, yet at the same time require a great deal of packaging investment.
Just a thought.
I have been getting a few questions lately from people curious about who I am and what my story is. One person said, “I am surprised just how little of yourself you put into your videos.”
For those curious, I recently went on the “But Then How?” podcast and talked about the channel and life in Asia. Great time. There a part two as well, which is coming next week.
Let me ask you something. You probably have heard all the news about this or that car factory shutting down because of the global chip shortage. That nobody can get the car they want because of a tiny little chip.
And you might be wondering. When did semiconductors matter so much to today's vehicles?
Why do we need to turn our cars into computers? Why can't things just be simple? What are all these electronics actually *doing* for our cars?
In this video we are going to go into the automotive supply chain and their semiconductors. The specific focus will be on conventional cars. But if this video does well enough, perhaps we can do a version for electric and autonomous vehicles.
Before we start, I want to note something. I am not a car guy. Living in Taiwan, I don't even own a car and I am a stereotypically bad driver. Automobiles are a massive field and as always, generalizations must be made. And exceptions will always abound. So keep that in mind.
A Brief History of Automotive Microcomputers
Our story begins in 1908 with the Ford Model T, a major landmark in the history of automotive vehicles. Cars then were entirely made up of mechanics. God’s in His heaven, all’s right with the world.
Shortly thereafter, electric light bulbs began showing up in headlamps and starter motors replaced hand cranks. This was the first piece of electronics incorporated into a vehicle. But other than that, cars remained mostly mechanical objects into the 1950s.
With the invention of new microelectronics technology and larger batteries, carmakers started adding automotive computers into their vehicles in the late 1960s. The first usage of such was for a fuel injection system by Bosch for a 1968 Volkswagen car.
Then in the late 1960s and 1970s, car manufacturers started widely adopting electronics for the purpose of controlling the air to fuel ratio.
Electronic fuel injection was a major breakthrough and would lead to the wide usage of electronic control units or ECUs.
The 1980s then saw an influx of electronics into your cars. Digital meters systems, information displays, airbag deployment systems, and antilock brake systems. All of these are today possible because of vehicle microelectronics and their semiconductors.
Today, semiconductors and microelectronics are thoroughly permeated throughout your conventional internal combustion cars. And the trend has only accelerated in recent years.
Modern, high-end cars have over 100 electronic control units or ECUs, running 100 million lines of code.
To compare, as of 2020, Windows has about 55 million lines of code and MacOS, 87 million lines.
The F-35 fighter jet has just 35 million lines.
Google however has them all beat with 2 billion lines of code across their various services. So that's nice.
Electronic wiring alone is estimated to add 45-65 pounds to each vehicle. Microelectronics make up a significant percentage of a vehicle's total cost. And the number is growing. Estimates find that number to be as high as 50% by 2030.
Semiconductors also help power the various sensors that exist within your car. Pressure, acceleration, power, and magnetic sensors - they all depend on semiconductors. Without them, you and the ECUs operating your car are running blind.
The reasons for this semiconductor invasion have to do with steadily increasing industry demands to improve vehicle performance, fuel economy, emissions, safety, and comfort. Basically every part of what makes a car worth owning and driving.
The fact is that electronics exist because mechanics alone have not been able to meet the requirements that manufacturers need them to. By intertwining the two, the final product can perform so much better than the either of them can by themselves.
Engine Emissions and Efficiency
For instance, let us talk about emissions and fuel efficiency. Controlling engine performance and emissions were the first big reasons why electronics started to show up in automotive vehicles. The killer app.
Engines work by combining air and gasoline and combusting them. Push down on the throttle and you are essentially asking to feed the engine more air to combust. Cars emit exhaust because this combustion reaction is not perfect. Accordingly, exhaust is made up of carbon monoxide and various nitrogen oxides and unburnt hydrocarbons.
In the late 1960s and 70s, policymakers passed new regulations for vehicle exhaust and fuel economy in response to health and environment issues from excessive vehicle pollution. The government tests these cars by putting them on a treadmill, simulating various trips, and measuring the emissions.
Automakers found that mechanical, hydraulic or pneumatic controls failed to achieve enough accuracy and consistency over each vehicle's usage life to meet these emissions tests. This was especially the case as the car aged.
With a microcomputer-powered ECU, automakers found that they can now carefully regulate the amount of fuel fed into the engine so that it properly matches with the air intake.
Furthermore, and this matters more than you think, they can implement the same ECU across all of their vehicles - SUVs and sedans alike - to gain advantages of scale and save on cost.
What started out as a separate sub-system for regulating these functions eventually evolved into an integrated digital system. Today you can argue that your belching, disgusting dinosaur-burning car engine is as digital as your slick glass iPhone.
Today, people like their cars to be safe. Feels like an important pre-requisite. Over time, automakers found that they can deploy electronics to help make their products safer. To not only protect their occupants in case of an accident but also to prevent them from ever happening.
For instance, the simple airbag. Simple in concept, but as it turned out, extremely difficult to implement.
The first airbags, introduced in the 1970s, operated with electromechanical switches. This is how it works.
Normally the switch is open.
But when deceleration forces get very high, it closes.
Once it closes, the completed switch is now able to send an electric current to the air bag igniter to ignite the air bag.
This took about 30 to 40 milliseconds to deploy. Which sounds fast.
But this turned out to be insufficient. Hm, no. I am being euphemistic. A lot of people still died in car crashes.
As it turns out, 40 milliseconds is fine for a 15 mile per hour collision into a frontal barrier. The requirement is about 50 milliseconds.
But the same type collision at 35 miles per hour needed a deployment of 18 milliseconds to save the life of its passengers. And electromechanical switches were not fast enough for this.
Today, ECUs are capable of constantly monitoring vehicle speed and deceleration from various angles. Then they can use algorithms to accordingly adjust airbag deployment and inflation.
Furthermore, they can incorporate data from gyroscopes to determine if the car is going to roll over. The ECU and its algorithms can then decide to also deploy the side air bags, tighten seat belts, and more. This has offered significant safety benefits and saved countless lives.
Let us go to the aforementioned ECU, the systems overseeing all of these functions. Modern vehicles have up to 150 of them, and they are responsible for controlling the various systems and subsystems within the car.
There seems to be an ECU for everything. I already mentioned their role in helping engines regulate their emissions and fuel efficiency as well as controlling the airbags for safety. But there are also ECUs for the brakes, powertrain, adaptive cruise control, electronic stability control, and powersteering.
I won't talk about all those. Here is one that I do want to talk about: ECUs that control the doors - the Door Control Unit or DCU.
They help roll the windows up or down. They deal with the child lock safety features, driver door switch pads (where you can control the rest of the car's windows), and global open-close functionality.
Your door would not work anywhere near as well without that DCU. And it is kind of funny because when I was a kid, I always thought that it worked because of long wires and little elves.
ECUs have come a long way since their invention over thirty years ago. Their functionality and complexity have greatly advanced. Despite this, to this day they still largely work the same way.
At the heart of it, the ECU is a simple thing - hardware on a PCB running low level software. It has sensors, control circuits, a power source, and an actuator driver - a component which is responsible for moving another mechanism.
Here is how it all works, conceptually. Sensors feed data on things like the crankshaft, airflow, or temperature into input processing circuits.
The control circuits - today it would be a micro-computer with a CPU, memory, timer, and I/O - receives data from these circuits.
They decide a proper output, which is then fed into output processing circuits which then go to your actuator. The drive then performs the actual action required for proper operation.
Within the ECUs themselves are microcomputers and the semiconductors that run them.
The semiconductors that operate these electronics are different from the types that go into your computer or mobile. One of the defining differences has to do with the harsh operating conditions.
It is not exactly the surface of Venus, but conditions are not cushy at all. Temperatures can reach 257 degrees Fahrenheit (125 Celsius) in the engine compartment, or negative 40 degrees Fahrenheit in the winter.
Rapid temperature swings can cause either the packaging or the chip itself to delaminate or even crack under the strain.
Relative humidity can be from 60-90%.
This can lead to moisture issues, a common point of failure. You don't need a wild imagination to visualize how water and moisture can finagle with a semiconductor.
Voltages from the battery can come unevenly and wildly fluctuate. These can cause damage to the pins and bonding, another common point of failure.
And then there is the turbulence from vibrations - 50Gs, 10x the consumer requirement. You have to make sure that a rough speed bump does not cause your car to break down.
Another unique concern for these semiconductors has to do with their reliability. Automotive suppliers require 20 year duration lives, twice that of what is required in consumer markets.
The way these systems are integrated within the car, they are not particularly easy to replace. And a driver might engage a brake tens of thousands of times over the lifespan of a car. It is necessary to ensure that the semiconductors running the brake ECU work every time, all the time.
This is all on top of the ordinary business requirements of being a component supplier to a big rich company. Always have to have better performance, more memory, zero defects, low power consumption, and ever lower prices. Oh, and it has to be done yesterday.
The niche aspects of these ECUs and their semiconductors can cause problems when their supply get disrupted. For instance, in March 2011 a major earthquake hit Japan.
Toyota Motors' Japanese factories survived the initial quake just fine. But its suppliers were hit bad and saw their production disrupted. In April 2011, Toyota’s car production levels fell by up to 78% from the previous year when their parts inventories came up empty. Sounds familiar?
Toyota initially did not even know what it was missing. It took a week to inventory the 500 parts from 200 locations that it needed to finish its cars. They include rubber bits and the like. But the most prominently missing components were the semiconductors for their ECUs.
The company had diligently diversified its first-tier ECU suppliers over the years. First-tier, meaning the suppliers they buy directly from. In 1992, 74% of its supply came from a single company, Denso. But by 2007, they reduced that to 47%. Mission accomplished, right?
As it turns out, both Denso and the other first-tier suppliers - Kehin and Hitachi Automotive - all depended on a single semiconductor company: Renesas Electronics. One of the company’s plants in Naka had been responsible for 15% of total capacity and was severely damaged.
It took about 3 months for them to get back to speed. Partly by tapping emergency capacity from various independent foundries - doubling their contribution from 10% to 20%. But automotive ECU makers personally oversee and certify the production of their semiconductors and foundries cannot easily change their lines to accommodate.
This exact sort of situation - where a company thought their first-tier suppliers were diversified but as it turns out they were all incestuously dependent on a single core supplier - has happened more than a few times. With Aisin Seiki's Kariya plant in 1997. With Riken's Kashiwasaki Plant in 2007. And so on.
I talked about it in a previous video about TSMC's earthquake threats. And judging by how the situation keeps happening over and over again around the world, it makes me think that companies are more willing to accept the significant but intermittent risks of this centralization rather than eat the substantial costs of true diversification.
So. In conclusion. Why can't a car just be "simple"? Asking the question, I think goes to show just how well the electronics have worked out. It works so well that people do not even know it is working so well for them.
It would be a misconception to look at your standard internal combustion car as a fundamentally mechanical device. Today's cars are some of the most complex electronic systems mankind has ever made.
They combine knowledge from across dozens of technologies and disciplines to make for a smooth, wonderful drive every day for years on end.
Over time, this has also required an increasing degree of specialization to allow these cars to perform so well and so reliably. And this has created situations where a single point of failure or overload can cause knock-on effects that cascade around the entire world.