CMOS power amplifier firm raises $35 million

April 18, 2016 // By Peter Clarke
Acco Semiconductor Inc. (Sunnyvale, Calif.), a private company that was founded near Paris in 1994, has raised $35 million to accelerate sales and development of its CMOS RF power amplifier and other front-end circuits.

This is one of the largest rounds of funding for a fabless semiconductor company in recent years and it brings the amount raised by Acco over the last decade to about $70 million from investors including Pond Ventures, Partech Ventures and Foundation Capital. BPI France has led the latest financing round.

Acco was founded by Denis Masliah, who serves as chief technology officer. He had previous experience designing RF and microwave circuits for Thomson CSF, Raytheon and Philips.

Acco has developed and patented a design of transistor that delivers performance similar to that of gallium arsenide but in a CMOS fabrication process. In October 2015, Acco announced the start of mass-production of its AC26120, A CMOS multimode, multiband PA for smartphones and Internet of Things (IoT) applications.

The transistor offers highly linear performance and can operate at high power without breakdown or degradation. The use of CMOS RF front-ends is expected to reduce size and cost for applications in smartphones and IoT. However, achieving similar performance to GaAs has provide difficult. One problem has been that impedance mismatch between PA and antenna can result in high instantaneous voltages across the PA. In GaAs, with a breakdown voltage of around 14V, it is possible to make robust devices that can survive.

Strategy analytics estimates that the annual market for mobile power amplifiers is $3.5 billion.

From 1994 to 2007 Acco was based at locations around Paris and operated as a service company and designed a number of high frequency chips that went out under semiconductor company brands. It was at around 2007 that Acco started filing patents on its CMOS power amplifier ideas.

The latest round of funding is intended to provide working capital as well as R&D funds for the next-generation product while enabling the company to add local support for its increasing customer base.

"We are excited to be investors in Acco whose revolutionary cellular radio component dramatically reduces