Glenn Collinson, a non-executive director at Wolfson Microelectronics, spent £86,000 on shares in the chip designer.He took 40,000 at 215p a time, having previously had none. Collinson co-founded the Bluetooth chip specialist Cambridge Silicon Radio (CSR, now a listed company) in 1998. Prior to that he worked at the US technology company best-known in the UK for its calculators, Texas Instruments.Wolfson Microelectronics has been in a slump since the middle of February but the share price got a fillip from the chip designer's first quarter results. Revenue in the first three months of 2011 rose 44% to $41.1m from $28.5m a year earlier, and a tad ahead of market consensus of $41.0m. Sales more than doubled year-on-year in mobile phones, particularly smartphones, gaming, eBooks and PC/tablets, the company said. The underlying operating loss narrowed to $0.9m from a loss of $4.9m. The market had been expecting an operating profit of $0.4m. With exceptional items such as amortisation of intangible assets included, the operating loss contracted to $3.4m from $7.1m. Top Director BuysWolfson Microelectronics (WLF) Director name: Mr Glenn CollinsonAmount purchased: 40,000 @ 215.00p Value: £86,000UK Coal (UKC) Director name: Mr Keith HellerAmount purchased: 170,128 @ 40.00p Value: £68,051STV Group (STVG) Director name: Mr David James Buchanan ShearerAmount purchased: 10,000 @ 148.00p Value: £14,800