Differential Sigma-Delta Capacitance Sensing Devices And Methods

A capacitance sensing device can include a reference circuit configured to connect to a reference capacitance, and to generate an electrical reference signal that varies over time according to the reference capacitance and a compare signal; a sense circuit configured to connect to a sense capacitance, and to generate an electrical sense signal that varies over time according to a sense capacitance; a compare circuit having compare inputs coupled to receive the sense signal and the reference signal, and a compare output that provides the compare signal; and a value generation circuit configuredto generate an output value corresponding to the compare signal over a predetermined time period. 电容感测设备可以包括：参考电路，其被配置为连接到参考电容，并且生成根据参考电容和比较信号随时间变化的电参考信号；感测电路，其被配置为连接到感测电容，并且生成根据感测电容随时间变化的电感测信号；比较电路，其具有耦合以接收感测信号和参考信号的比较输入端以及提供比较信号的比较输出端；以及值生成电路，其被配置为在预定时间段内生成与比较信号相对应的输出值。