An integrated CMOS Wide Band Arbitrary Waveform Generator (AWG) for Carrier Aggregation purpose is proposed and demonstrated. This work is designed to target the sub-6 GHz 5G standard and is implemented in 65nm CMOS technology from TSMC. A piecewise linear approximation of the modulated signal, using Noise Shaping Riemann (NSR) algorithm, is processed. Its principle is based on the integration of constant current steps into a capacitive load. Moreover, the ability to generate multi-carrier signal is also demonstrated with measurements of a minimum 28dB SNDR on multi-carrier signal confirming the theory. EVM measurements depict a maximum of 16% for a data rate of 50MS=s for carrier frequencies up to 3:2Ghz. The Riemann Pump consumes less than 1mW for a reduced die area.