Current/Voltage Dual-Mode Single-Wire Simultaneous Bidirectional Interface Architecture for Sensor System.

Area of Science:

• Electrical Engineering and Computer Science
• Integrated Circuit Design
• Sensor Systems

Background:

• Traditional sensor systems often require multiple wires for data transmission, increasing package pin counts and system complexity.
• Efficient and low-power communication interfaces are crucial for miniaturized sensor integrated circuits (ICs) and system-on-chips (SoCs).

Purpose of the Study:

• To propose and validate a simultaneous bidirectional asymmetrical serial interface architecture for sensor systems.
• To develop a current/voltage dual-mode signaling scheme for synchronous clock and continuous data transmission using a single wire.
• To minimize pin requirements for sensor IC and SoC packages.

Main Methods:

• Implementation of two transceiver circuits in 65 nm CMOS technology for sensor IC and SoC.
• Design for specific transmission rates (1 Mb/s and 250 Kb/s), core areas, and power consumptions.
• Application of the sensor IC transceiver to a monolithic photoplethysmography (PPG) sensor in 180 nm CMOS.

Main Results:

• Successful acquisition and transmission of PPG sensor data using the developed transceiver circuits.
• Transceiver circuits achieved transmission rates of 1 Mb/s (SoC) and 250 Kb/s (sensor IC).
• Low power consumption (7.1 μW for sensor IC, 145.8 μW for SoC) and small core areas (0.008 mm² for sensor IC, 0.142 mm² for SoC) were demonstrated.

Conclusions:

• The proposed serial interface architecture effectively enables efficient, single-wire communication between sensor ICs and SoCs.
• The dual-mode signaling scheme reduces pin count and power consumption, making it suitable for advanced sensor applications.
• The successful integration with a PPG sensor validates the architecture's practical applicability.