Patent ID: 11954287
Assignee: SHENZHEN GOODIX TECHNOLOGY CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A multi-branch alternating-current-mode (AC-mode) bridge for self-capacitor sensing, the multi-branch AC-mode bridge comprising:
K branches, each to couple with a respective one of a plurality of touch sense channels of a touch panel array integrated with a display panel, K being an integer greater than two;
K adjustable current sources, each to output a respective one of K sinusoidal input currents based on an error signal;
a unit current rotator having K rotator inputs and K rotator outputs, each of the K rotator inputs coupled with a respective one of the K sinusoidal input currents, each of the K rotator outputs coupled with a respective one of the K branches, the unit current rotator configured to cycle repeatedly through a sequence of K frames of a rotation cycle, each frame defining a unique set of one-to-one couplings between the K rotator outputs and the K rotator inputs, such that each of the K branches receives a respective sinusoidal branch current that is sourced by each of the K sinusoidal input currents for 1/Kth of each rotation cycle; and
an error amplifier to generate the error signal responsive to a sinusoidal driver signal and a channel feedback signal,
wherein each of the K branches manifests a respective branch voltage responsive to its respective sinusoidal branch current, and the channel feedback signal is based on the respective branch voltage from one or more of the K branches.