Ring oscillator based all-digital Bluetooth low energy transmitter
US10567154B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 2018 |
| Grant date | Feb 18, 2020 |
| Priority date | — |
| Expiry date | Nov 21, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/451
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A Bluetooth Low-Energy (BLE) transmitter is presented for used in ultra-low-power radios in short range IoT applications. The power consumption of state-of-the-art BLE transmitter has been limited by the relatively power-hungry local oscillator due to the use of LC oscillators for superior phase noise performance. This disclosure addresses this issue by analyzing the phase noise limit of a BLE TX and proposes a ring oscillator-based solution for power and cost savings. The proposed transmitter features: 1) a wideband all-digital phase locked loop (ADPLL) featuring an fRF/4 RO, with an embedded 5-bit TDC; 2) a 4× frequency edge combiner to generate the 2.4 GHz signal; and 3) a switch-capacitor digital PA optimized for high efficiency at low transmit power levels. These not only help reduce the power consumption and improve phase noise performance, but also enhance the transmitter efficiency for short range applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.