Results from MPGDs with a protected timepix or medipix-2 pixel sensor as active anode

The functioning of a high-resistive, hydrogenated amorphous Silicon layer as a protection against discharges for Micoomegas-based pixel readout gaseous detectors, has been investigated. Chips, protected with a 3 mum thick layer, still broke, but a 20 mum thick layer has proven to be adequate. Images from discharge events disclose their geometrical parameters, enabling to further optimize the discharge protection.