Design of a GNSS Signal Synchronization Chip

The 1PPS timing signal sent by GNSS has high precision and stability, so it can be used as a reference signal for a variety of purposes. This GNSS signal synchronization chip can synchronize the locally produced second cycle signal with 1PPS signal, which includes a hierarchical Time-to-Digital Converter (TDC) and a two-stage phase-shifting unit. The chip is implemented in 0.18μm 1P6M CMOS technology, and power voltage of core is 1.8V and normal operating temperature range is from -40°C to 125°C. Test results show the dynamic power current at work is about 4mA, while the static power current at low power consumption is about 32μA. The minimum time resolution is about 1ns.