02.19.16
Imec and Vrije Universiteit Brussel (VUB) have demonstrated a 0.22mm2 CMOS resistive charge-based direct launch digital transmitter with -159dBc/Hz out-of-band noise. The achievement paves the way to small form-factor SAW-less transmitter implementations enabling advanced wireless communication systems including all the cellular standards 3G, 4G and future 5G.
Analog transmitters are less suitable for integration in advanced CMOS nodes. Digital transmitters are more compact and more robust to transistor imperfections and mismatches compared to analog transmitters, but they typically fall short with respect to high-end performance requirements such as out-of-band noise and spurious emission.
Imec and VUB overcome this with a new transmitter architecture that combines the best of both worlds. The incremental-charge-based digital-to-analog (QDAC) conversion allows full direct digital control of the transmitted signal, while at the same time enables intrinsic noise filtering that reduces out-of-band noise and alias components to state-of-the-art levels.
Analog transmitters are less suitable for integration in advanced CMOS nodes. Digital transmitters are more compact and more robust to transistor imperfections and mismatches compared to analog transmitters, but they typically fall short with respect to high-end performance requirements such as out-of-band noise and spurious emission.
Imec and VUB overcome this with a new transmitter architecture that combines the best of both worlds. The incremental-charge-based digital-to-analog (QDAC) conversion allows full direct digital control of the transmitted signal, while at the same time enables intrinsic noise filtering that reduces out-of-band noise and alias components to state-of-the-art levels.