Control Data is selling its holdings in Centronics.

The Minneapolis computer company said it would dispose of its 26% share of the smaller firm through the sale of stock and convertible subordinated debentures worth a total of about $25 million. Control Data recently sold its Ticketron business as part of a plan to trim its debt and losses. In a separate announcement, Control Data and N. V. Philips said they expect to finalize by June 30 their joint venture to develop and market devices, most likely compact disks, for information storage.