Remembering and Honoring Dr. Hayashi: Lessons from a Great Mentor

I recently learned about the passing of Dr. Hayashi. Hayashi-san is regarded as the greatest teacher, coach, and role model for many generations of engineers who began their careers in the semiconductor industry with Renesas Vietnam Company (RVC), including myself. While I feel deeply saddened by this shocking news, it was also a nostalgic and emotional experience reading so many heartfelt condolence messages and tributes from engineers whose lives he touched. In the end, everyone will pass away, but their legacy and impact will last forever. As someone fortunate enough to be trained by him at the beginning and coached by him for several years while working as an RTL design course training assistant, I’d like to express my tribute to Dr. Hayashi too.

On this occasion, to honor his memory and share his wisdom with younger generations who never had the chance to meet him, I would like to share the most memorable lessons I learned—directly or indirectly—from Hayashi-san.

1.?????? The Power of Imagination

?As a young engineer, I thought imagination was only required for high-level jobs or when inventing something. But in fact, imagination is powerful and essential in all execution-level jobs, from design documents, RTL code, to verification, synthesis, DFT, STA, PnR, etc. For example, a person who writes design documents should use their imagination to consider several design options to implement a target specification from the architecture team or customer. Good designers should also challenge the architecture team or even educate the customer on better ways to define a product. Similarly, the verification team should at least challenge the RTL designers, and so on for all other disciplines throughout the chip development flow. With the high cost of advanced nodes nowadays, this lesson is even more important because I think it’s one of the key elements to achieve the first tape-out to production goal.

2.?????? The Power of Little Effort Every Day

Probably the simplest way to understand this is the formula 1.01^365 = 37.78. But another subtle point I’d like to mention is that back in my days, and even nowadays, no matter your scores or which university you graduated from, you are virtually at the same starting line when you start a job. And with AI, maybe all of us, regardless of our experiences or locations, will have to start again.

3.?????? Attention to Detail

I still remember countless times Dr. Hayashi-san spent extra time diligently correcting some drawings in the slides to make them better based on feedback from students in the morning sessions. Another time, he spent even more time ensuring the engineers understood subtle points in “System Verilog” signed and unsigned matters. The most memorable is when I saw his emails to trainees saying, “Do not assume your code is okay just because the simulation passed.” Another point is that I observed several engineering leaders/managers who spent significant time honing soft skills may think a generalization mindset is more important. They tend to trust their guts and downplay the details. I think it’s a pitfall. For those who want to investigate more about this, I recommend the book “Only the Paranoid Survive” by Andy Grove, who mentioned that “the devil is in the detail.”

4.?????? The Power of Soft Skills

I guess 80% of engineers (including myself) don’t spend time on soft-skills development early in their careers. Even a few people are “allergic” to the keywords “soft skills.” A common pitfall is that several think soft skills are only for the managerial path, not the engineering path.

I worked with Hayashi-san on revising (a kind of finding bugs) the Verilog design textbooks every time we started a training session for fresh engineers. These were such huge books that we needed to distribute the tasks to several experienced engineers. The striking fact I learned is that Hayashi-san had a background in software, not hardware design. Many contents of the books were collected from different hardware experts. But one thing I believe is that no one could teach such knowledge to young engineers better than Hayashi-san. I think it’s a testament to the power of little effort, attention to detail, but foremost, his soft skills.

For technical path engineers who practice running, you can imagine soft skills like “cross-training” or “gel.” You don’t need such things if you aim to finish a 5K or even a 10K, but to finish a marathon or a good half-marathon, such things are indispensable.

It’s not from Hayashi-san, but from another very senior colleague I met last year: Technical (or hard) skills are often difficult to carry with you when changing jobs, but soft skills will stay with you for life.

But hold on, what are soft skills? To me, whatever is not hard is soft, even including guitar skills, table tennis skills, and "go" skills, you name it. I still remember how fun and admirable it was playing table tennis with Hayashi-san during our lunchtime at RVC.

5.?????? The Power of Silence

Before sharing a bit more on this, I should admit that I was very bad at controlling my temper during communications for the first decade of my engineering career. Even after I became a manager, receiving much feedback from my peers and witnessing some people who are willing to give advice to others even when the receiver does not want to receive it, I still didn’t get it until I had a chance to listen to THIS video during the last Lunar New Year holiday.

As far as I remember, I think Hayashi-san never taught me this lesson directly. But remembering working with him, I think he was a “strict” teacher. He was somebody that I felt I had to do my homework before asking him. But unlike the “strict” teachers I met in secondary school, high school, and university, or any noisy “leaders/managers” I’ve worked with, I think I listened to him most or regarded him most not because he said it loudly, but because he said very little or nothing at all. For people who want to improve their communication and coaching skills, I strongly recommend THIS another video. I think no matter what I tried, I’ll never become a great coach like Hayashi-san. But I hope I’ll improve my coaching skills over time and can help the next generation to my limit.

Hayashi-san, hontō ni arigatō gozaimashita., for being a great teacher, mentor and coach to me. May you rest in peace!

P.S. It’s a pity that I don’t have any pictures with Dr. Hayashi. So, I asked AI to generate an image of the event where he gave me the “Ichiban” T-shirt as a gift for an RTL contest back in my RVC days. Many years have passed, but I still remember that day as a highlight of my career. Thank you again.