Aimed at Power Distribution, Menlo Micro Debuts “Highest” Power MEMS Switch
Putting its Ideal Switch technology back into action, Menlo Micro has unveiled what it says is the industry highest power MEMS switch device.
As the electrification of all things moves into fast growing markets like EV chargers, solar panel electronics, and industrial automation, the old ways of power distribution aren’t cutting it. Feeding that need, today Menlo Micro has released what it claims as the industry’s first MEMS (microelectromechanical system) power switch, capable of handling 10 A in a miniature 5 mm x 5 mm surface-mount package.
Offering an extremely low contact resistance of 10 mΩ, the company claims the MM9200 as the world’s lowest-loss and highest power capable MEMS switch.
Getting a sneak preview of the MM9200 MEMS switch, All About Circuits’ Editor-in-Chief Jeff Child talking to Chris Giovanniello at Menlo Micro’s booth at Electronica last month.
In this article, we outline the problem the MM9200 MEMS switch solves for engineers, examine the details of the device, and we share perspectives from our interview with Chris Giovanniello, Menlo Micro’s co-founder and senior vice president of marketing.
Replacing Mechanical Relays in Power Distribution
Even in today’s world of advanced electronics technology, Giovanniello points out that at least 80% of today’s power distribution is still done with old-fashioned mechanical relays—a technology that hasn't changed much in over 100 years.
“Those are very nice from an electrical perspective because you have that metal-to-metal contact,” says Giovanniello, “But the form factors that you have with mechanical relays are large, and the lifetimes that they have are a problem because they can only operate in thousands of times before they wear out and have to be replaced.” That situation is unacceptable for today’s trends with the future electrification of the world where you want to manage power loads constantly.
“You want to be able to turn things on and off. You want to be able to monitor what's going through them and have that control at the load. And you can’t do all that with a mechanical relay technology that was invented in the 1890s.”
The MM9200 provides a MEMS solution that accommodates thermal management by not generating as much heat in the first place as mechanical relays. Image used courtesy of Menlo Micro
Meanwhile there’s been a push to replace those mechanical relays with semiconductor-based solid-state relays, but those have their own limitations. The problem with going to semiconductors is that they're by definition “conductors”, says Giovanniello.”When you're using them for these applications, you dissipate a lot of heat.”
With all that in mind, Giovanniello says that, with the MM9200, Menlo Micro is trying to solve the challenge of combining advanced features, miniaturization, and reliability for power distribution and controls, but doing so without paying the penalty of losing efficiency. Mechanical relays have to use bulky thermal management methods such as heatsinks. In contrast, Menlo Micro’s approach is to not generate the heat in the first place.
Based on Menlo Micro’s “Ideal Switch” Technology
The MM9200 is based on Menlo Micro’s Ideal Switch technology. Earlier this year, the company introduced the MM5140, a device using Ideal Switch technology aimed at RF switching. According to the company, the Ideal Switch’s scalable design and process technology provides extreme mechanical endurance typically in the billions of switching cycles. That’s a thousand times better lifetime than traditional electromechanical relays, says the company.
Giovanniello says this reliability, combined with its arc-free capability, helps reduce unplanned maintenance and replacement costs. The device has a 10 µs actuation speed which is more than 1,000x faster than its electromechanical alternatives. An animation on the company’s site shows how the “Ideal Switch for Power” technology works.
The MM9200 integrates over 400 individual switches to support kilowatts of power in a tiny QFN or WL-CSP package. Image used courtesy of Menlo Micro
According to Giovanniello, the MM9200 breaks new ground because it integrates more than 400 individual switches to support kilowatts of power in a small surface-mount package. Similar to the company's other Ideal Switch products, the MM9200 makes use of metal-to-metal contacts. These reduce losses and power dissipation by more than 90% when compared to solid-state devices, says Giovanniello. More information is available in the MM9200 datasheet.
MM9200 key features include:
- On-state resistance: 10 mΩ
- Continuous carry current (AC or DC): ±10 A
- Voltage standoff (AC or DC): ±300 V
- Switching time: 10 μs to open, 10 μs to close
- Mechanical endurance: 1 billion switching operations
- Package options: QFN and low-profile 5 mm × 5 mm WL-CSP
The MM9200 is also an alternative to MOSFET switches. In contrast to MOSFETs, the MM9200 supports bidirectional current between contacts just like electromechanical relays do. The company says that the internal dual gates are controlled via the common “GATE” pin and requires a gate bias voltage in relation to the “MIDPOINT” pin to turn on the switch. Engineers can use multiple MM9200 devices connected in series to increase voltage, or in parallel to increase current rating.
A Solution for Today’s Fast Growing Power Applications
The applications for which a product like MM9200 are vital just happen to some of the hottest emerging growth markets. Systems such as EV charging stations, smart power grid systems, solar energy inverters, and more all need high-current, high-voltage power distribution. Perhaps the MM9200 can provide a solution for such system designs, in a reliable, long-life form factor.
Menlo Micro’s CTO Chris Keimel was our Moore’s Lobby podcast guest earlier this year.
