By Mark Emmons

SANTA CLARA — Jeff Miller was telling a story about how he and his wife, Karen, once were in a cobra-infested part of Cambodia, wearing protective body armor and helmets, carefully treading through a minefield.

Then he stopped. Miller knew how ridiculous that must sound.

“At this point, your readers might say, ‘This guy is an idiot. No wonder he’s giving his money away,’ ” he said with a laugh.

Miller is not crazy and he’s not giving away everything he’s made during a successful career as a Silicon Valley executive, either.

But he and his wife are donating $25 million to Santa Clara University and the now renamed Miller Center for Social Entrepreneurship that has created a unique, good works program championed by the couple. It is one of the largest gifts in school history.

The Global Social Benefit Incubator mentors grass-roots entrepreneurs striving to make a difference with businesses that provide clean water, efficient energy, healthful food and, yes, soil cleared of deadly land mines in some of the globe’s most impoverished regions. So far, 340 entrepreneurs in 55 countries have been shown how to expand their companies to have the greatest possible impact.

“Karen and I feel like we’ve been blessed,” said Miller, 64. “We just think that somebody in that position has an obligation to give back. We want to help people who are the most needy and in a way that utilizes how we got where we are — through innovation and entrepreneurship.”

Miller is outgoing and energetic — the kind of person who you would expect to be a business leader. His wife, on the other hand, is much more reserved and uncomfortable about being in the spotlight. But she’s agreed to be so public about this gift in hopes of attracting the attention of others who also have benefited from Silicon Valley’s wealth-generating machine.

“The Valley really has changed the world,” said Karen Miller, 57. “If we could just corral some of that spirit and look beyond our own backyard, we can change the world in a different way by helping people live in a more dignified manner.”

The idea of “giving back” has become a hot-button topic as new-money tech titans increasingly have drawn criticism for not being more philanthropic with their millions — and in some cases billions.

The Millers don’t do criticism. They’re just hoping to inspire.

“There are enormous problems of poverty around the world, and Silicon Valley can leverage philanthropy to do enormous good,” added Thane Kreiner, the center’s executive director. “What Jeff and Karen like about this program is that we’re doing it by using the same market systems and innovation that created the Valley.”

Kreiner, by the way, is the one who coaxed the hands-on Millers into that Cambodian minefield.

“Probably not the smartest thing that I’ve ever done,” Kreiner conceded.

The 64-year-old Miller’s varied career has touched most of the Silicon Valley ecosystem. The East Bay native and Santa Clara graduate held senior executive positions at high-tech companies, worked in venture capital and today calls himself a “professional board member,” helping oversee seven companies and organizations.

After retiring as CEO of the software company Documentum in 2001, Miller looked for new challenges. He was intrigued at how his alma mater’s Center for Science, Technology, and Society was working to eradicate poverty by combining smart business solutions with the Jesuit philosophy of creating a more just, humane and sustainable world.

Local executives, volunteering their time, are paired with entrepreneurs who have created socially conscious products and services. As the Millers became more involved — Jeff is now chairman of the center’s board — they began taking “immersion” trips, visiting Africa and Southeast Asia, to personally see the results.

They’ve been on towering Mount Elgon, between the Uganda and Kenya borders, watching African women sell inexpensive, light-producing products door to door for the company Solar Sister. They’ve ridden on the back of motor bikes in rural Cambodia with Operation ASHA to make “last-mile” deliveries of tuberculosis medicine to patients. They’ve seen how APOPO uses trained African giant pouched rats — nicknamed HeroRATs — to sniff out the TNT in hidden land mines.

Karen Miller, a San Jose native who met her husband when they were working at Intel, said the minefield experience made her appreciate the rapid heartbeat farmers must feel when they’re planting crops, knowing that they could touch an explosive at any moment.

“There’s a reason why I call these entrepreneurs superstars,” she said. “They’re all amazing people who do such good work.”

Katherine Lucey, the founder of Solar Sister, said the Santa Clara program was a well-timed boost to their development. The company now has 1,300 entrepreneurs bringing light to more than 250,000 people each day.

“The Millers are true philanthropists, investing time and money in the causes that they care about,” Lucey wrote in an email from Tanzania. Their support, strategic thinking and compassion, she added “results in real-world impact.”

The Santa Clara center’s goal is to help companies positively impact the lives of 1 billion people by 2020.

“You’ve heard the expression about giving a man a fish, feed him for a day, but teach a man to fish, feed him for a lifetime?” Miller asked. “Well, teach him how to run a fishing business, you can keep a village running for a lifetime. That’s what we’re trying to do — build scale.”

The idea is that the gift, which was announced Thursday night at a gala on the Santa Clara campus, will create a domino effect and have benefits that can’t even be envisioned today.

But waiting until tomorrow to do something is not an option, Miller said.

“When you go to these places, you realize that the time to solve things is now,” he said. “Actually, it was yesterday. Time is not our friend.”

Follow Mark Emmons at Twitter.com/markedwinemmons.