《STM32F0—触摸按键》.pdf

触摸感应控制器TSC 功能外设 电荷转移的过程 S2 Cx S1 S5 S6 S4 Cs S3 开关S4保持关闭状态 开关S5和S6保持断开 I/O register STEP 开关S3 开关S2 开关S1 DESCRIPTION 1 Closed Opened Closed Cs discharge 2 Opened Opened Opened Deadtime 重复这些步骤，直到 3 Opened Closed Opened Charge cycle (Cx charge) VCs达到高电平 4 Opened Opened Opened Deadtime Transfer cycle (charge 5 Opened Opened Closed transferred to Cs) 6 Opened Opened Opened Deadtime 7 Closed Opened Closed Cx discharge 1 通过电荷转移获得电容值的原理概述  利用电容储存电荷的特性  电极上的待测电容C 向采样电容C 充电 x s  电荷转移过程中个模拟开关是硬件做在GPIO里的  重复电荷转移的过程，直到采样电容C 上的电压达到 s 它说连GPIO的VIH 门限值  过程重复的次数就反映了待测电极上电容的大小  电极被触摸时，重复次数N减小 Charge cycle V DD Electrode capacitor charging V IH Charge transfer 2 电荷转移测量电路 STM32F051 Rs G1