Timepix is a pixel readout chip of size 14 x 14 mm containing 256 x 256 square pixels of 55 µm, and can be bump-bonded to several types of sensors. The Timepix chip is developed by the Medipix collaboration, derived from the Medipix2 chip which operates in photon counting mode. Every pixel in the Timepix chip can be configured in one of three operation modes.