Hybrid ΔΣ Programmable Phase/Frequency Detector for IoT Chipsets

A hybrid digital phase-locked loop (HDPLL) based constant-envelope modulator for Internet-of-Things (IoT) wireless connectivity technologies such as Bluetooth Low-Energy (BLE) and IEEE 802.15.4 ZigBee was recently proposed. It is built around a hybrid 2nd-order ΔΣ closed-loop phase/frequency detector (ΔΣ PFD) that facilitates analog quality detection of a radio frequency (RF) carrier and tracking of its frequency modulation. Addressing the IoT chipsets low-power consumption requirements, a passive ΔΣ PFD is presented that features programmable digitization resolution assisted by mixed-signal finite impulse response (FIR) filtering and digital noise cancellation.