VeloPix: the pixel ASIC for the LHCb upgrade. (30th January 2015) - Poikela, T.; Gaspari, M. De; Plosila, J.; Westerlund, T.; Ballabriga, R.; Buytaert, J.; Campbell, M.; Llopart, X.; Wyllie, K.; Gromov, V.; Beuzekom, M. van; Zivkovic, V.