Patent ID: 7812830

Claim:
An apparatus comprising: a plurality of pins; a switch network that is coupled to each of the plurality of pins; an analog-to-digital converter (ADC) that is coupled to the switch network; a controller that is coupled to the ADC; a pen-touch detector circuit that is coupled to the switch network; and a clock circuit having: a first circuit that is coupled to the pen-touch detector circuit, wherein the first circuit generates a clock start signal; an ANDing circuit that is coupled to the first circuit so as to receive the clock start signal; an resistor-capacitor (RC) circuit that is coupled to the ANDing circuit; an inverter that is coupled to the ANDing circuit; a buffer that is coupled to the RC circuit and the inverter; a second circuit that is coupled to the buffer and the pen-touch detector circuit; and a state machine that is coupled to the first circuit and the second circuit.