Dan Moloney, the president of Motorola’s set-top box unit, has left the company, the latest executive to move since the firm announced earlier this month its plans to split into two companies. Moloney will become CEO of Technitrol, an electronics-component manufacturer. Sanjay Jha, currently co-CEO of Motorola, will be the chief executive of the new business that will combine Motorola’s handset unit and set-top box division.