OptoIQ published an article on Philips silicon photomultiplier advantages. Philips places 1-bit ADC inside each pixel, that digitizes an avalanche PD output. There is also active quenching circuitry integrated into each pixel.
Philips' fully integrated 64 pixel sensor with a sensing surface of greater than 10 cm2 and a power consumption less than 15 mW/cm2 uses 180 nm CMOS technology on 8 in. wafers (to me this sounds like Tower is the foundry). The device's photon-detection efficiency is 30% at 450 nm; it has an optical crosstalk of 8% and a dark-count rate of 100 kHz/mm2 at 20°C and 900 Hz/mm2 at -40°C.