The AT84AS001TP is a monolithic 12-bit ADC with a clock frequency of 500Msamples/s, effectively allowing system designers to accurately digitise signals with frequencies up to 250MHz with one device and in one conversion. Typically, with 12-bit ADCs alternatives limited to 250Msamples/s, designers are forced to use several down-conversion hardware stages before entering the analogue signals into the ADC, and to interleave several ADCs to get high data rates. The chip has a 0.5dB band flatness from DC to 250MHz, and provides 62dBc SNR, 75dBc SFDR and 10 ENOB at 500Msamples/s over the first Nyquist zone, with two-tone inter-modulation distortion limited to -70dB. This is achieved while dissipating 2.3W with 3.3 and 5V power supplies. The required analogue input signal amplitude is only 1.1Vp-p, and can be AC- or DC-coupled.