US 12,487,688 B1
Touch controller synchronization with the downlink signal of stylus
Pan Wang, Shenzhen (CN); Yue Ding, Beijing (CN); and Bowei Chen, Shenzhen (CN)
Filed by STMicroelectronics International N.V., Geneva (CH)
Filed on Oct. 11, 2024, as Appl. No. 18/912,833.
Int. Cl. G06F 3/0354 (2013.01)
CPC G06F 3/03545 (2013.01) 20 Claims
OG exemplary drawing
 
15. A touch controller for synchronizing a synchronizing a stylus-enabled device with a stylus, the touch controller comprising:
an analog-to-digital converter (ADC) configured to sample a downlink signal received from the stylus;
an In-phase and Quadrature (I/Q) demodulator configured to extract magnitude and phase information from the sampled downlink signal;
a processor configured to:
determine a timing offset between an uplink signal transmitted to the stylus and the downlink signal,
determine a phase shift of the downlink signal based on the extracted phase information, and
adjust a synchronization timing based on the determined timing offset and the determined phase shift; and
a timing generator circuit configured to apply the adjusted synchronization timing to subsequent communications with the stylus.