US 12,326,995 B1
Touch detection circuit
Jia-Ming He, Tainan (TW); Yaw-Guang Chang, Tainan (TW); Zong-You Hou, Tainan (TW); and Yi-Yang Tsai, Tainan (TW)
Assigned to HIMAX TECHNOLOGIES LIMITED, Tainan (TW)
Filed by HIMAX TECHNOLOGIES LIMITED, Tainan (TW)
Filed on Jan. 10, 2024, as Appl. No. 18/408,605.
Int. Cl. G06F 3/041 (2006.01); G06F 3/044 (2006.01)
CPC G06F 3/0418 (2013.01) [G06F 3/0412 (2013.01); G06F 3/04166 (2019.05); G06F 3/0446 (2019.05)] 13 Claims
OG exemplary drawing
 
1. A touch detection circuit, comprising:
at least one driving signal generator, receiving a first power voltage and a second power voltage as operation powers, wherein each of the at least one driving signal generator generates at least one driving signal with a sine wave based on the first power voltage and the second power voltage, and an amplitude of each of the at least one driving signal swings between a first voltage and a second voltage, wherein the first voltage is a positive voltage and the second voltage is a negative voltage,
wherein each of the driving signal generator comprises:
a first signal converting circuit, generating a first converting signal according to a first input code;
a second signal converting circuit, generating a second converting signal according to a second input code;
a first voltage buffer, coupled to the first signal converting circuit and generating a first buffering signal according to the first converting signal;
a second voltage buffer, coupled to the second signal converting circuit and generating a second buffering signal according to the second converting signal;
a multiplexer, coupled to the first voltage buffer and the second voltage buffer, and generating the driving signal by alternatively selecting the first buffering signal and the second buffering signal;
a third signal converting circuit, generating a third converting signal according to a third input code;
a fourth signal converting circuit, generating a fourth converting signal according to a fourth input code;
a third voltage buffer, coupled to the third signal converting circuit and generating a third buffering signal according to the third converting signal; and
a fourth voltage buffer, coupled to the fourth signal converting circuit and generating a fourth buffering signal according to the fourth converting signal,
the multiplexer further generating the driving signal with a first phase by alternatively selecting the first buffering signal and the second buffering signal, or generating the driving signal with a second phase by alternatively selecting the third buffering signal and the fourth buffering signal,
wherein the first phase is different from the second phase.
 
10. A touch detection circuit, comprising:
at least one driving signal generator, receiving a first power voltage and a second power voltage as operation powers, wherein each of the at least one driving signal generator generates at least one driving signal with a sine wave based on the first power voltage and the second power voltage, and an amplitude of each of the at least one driving signal swings between a first voltage and a second voltage, wherein the first voltage is a positive voltage and the second voltage is a negative voltage, wherein when number of the at least one driving signal generator is larger than 1, the plurality of driving signal generators are grouped into N driving signal generator groups, wherein each of the N driving signal generator groups provides a plurality of driving signals, and a phase of at least one of the driving signals is set to a first phase and the other driving signals are set to a second phase, wherein N is a positive integer, and the first phase is different from the second phase.