4 GHz locking range and 0.19 pJ low-energy differential dual-modulus 10/11 prescaler

In this paper, we present a differential dual-modulus prescaler based on an injection-locked frequency divider (ILFD) for a satellite low noise block (LNB) down converter. Three stage differential latches using ILFD and a cascaded differential divider can achieve divide-by-10/11 operations with a lock range of 2.1 GHz - 10 GHz at a supply voltage of 1.4 V and an operating frequency range of 2.1 GHz - 6.1 GHz at a supply voltage of 1 V. At our target frequency, 5 GHz, a minimum energy of 0.19 pJ (=mW/GHz) at the maximum input frequency can be achieved. Our proposed circuit is fabricated by a 130 nm CMOS process, and the prototype chip core area is 40 × 20 μm².