2022-075 - Time-Domain ADC with a SAR TDC

Description:

 

Market Opportunity

The need for high-speed, medium-resolution analog-to-digital converters (ADCs) is rapidly growing due to the increasing demand for wideband communication integrated circuits. The traditional voltage-domain time- interleaved SAR time-to-digital converter (TDC) is an efficient option, but its single-channel sample rate is limited, necessitating a large number of TI channels. Recently, time-domain ADCs have shown promise in high- speed scenarios, but their circuit complexity grows exponentially with the target bit resolution.

USC Solution

USC inventors have developed a two-step time-domain ADC that reduces size, cost, and circuit complexity. The technology uses a first-stage Flash TDC with residue time quantized by second-stage SAR TDC to target the >GS/s regime and address the limitations of existing solutions. A proof-of-concept ADC prototype using this technology reaches 10GS/s with 37.2dB SNDR at Nyquist frequency while measuring an energy efficiency of 24.8fJ/conv-step. The device takes up an active area of 2850um2, the highest reported energy efficiency and smallest area consumption for state-of-the-art ADCs with greater than 10GS/s.

Value Proposition

  • Improved single-channel sample rate

  • Decreased circuit complexity and area consumption

  • Good energy efficiency

Applications

  • Wireless communication
  • Broadband wired communication systems

  • Radar and sensing systems

Publications

A 10GS/s 8b 25fJ/c-s 2850um2 Two-Step Time-Domain ADC Using Delay-Tracking Pipelined-SAR TDC with 500fs Time Step in 14nm CMOS Technology, Liu et al., 2022.

Stage of Development

  • Proof-of-concept prototype developed

  • Available for licensing

Patent Information:

  • Title: Signal Converter with Delay Architecture for Concurrent Signal Processing
  • App Type: Nationalized PCT
  • Country: United States
  • Serial No.: 18/719,024
  • Patent No.:  
  • File Date: 6/12/2024
  • Issued Date:  
  • Expire Date:  
  • Patent Status: Patent Pending