Raspberry Pi said Powell brings over 20 years' leadership experience across public companies. Most recently, he was CFO of Alpha Group, where he managed the company's move from AIM onto the Main Market of the London Stock Exchange and into the FTSE 250 and its subsequent sale to Corpay.
Boult will step down from his role as CFO on 31 October as part of an effort to facilitate a smooth transition.
Chairman Martin Hellawell said: "Tim brings deep experience of scaling fast growing businesses and navigating periods of significant strategic development. His track record at LSEG and Alpha demonstrates his ability to combine financial discipline and operational execution, and we are excited to welcome him to Raspberry Pi.
"As we continue to expand our global reach and invest in the opportunities ahead, Tim's experience and perspective will be invaluable to the business and to the board."
As of 0810 BST, Raspberry Pi shares were down 1.24% at 837p.
Reporting by Iain Gilbert at Sharecast.com
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