A touch driving device , in which one frame is time-divided into at least one touch driving period (TP) and a display driving period (DP) and which is configured to operate in the at least one touch driving period (TP), wherein the touch driving device is configured to generate a touch driving signal (TS) during the touch driving period (TP), apply the touch driving signal (TS) to a touch screen (TSP), sense a first pen driving signal (PD1) applied to the touch screen (TSP) from a stylus pen in a first period (SS1) of the touch driving period (TP), and sense a second pen driving signal (PD2) applied to the touch screen (TSP) from the stylus pen in a second period (SS2) of the touch driving period (TP), wherein the first pen driving signal (PD1) and the second pen driving signal (PD2) are synchronized with the touch driving signal (TS), wherein the first pen driving signal (PD1) is used to detect an active stylus pen touch input, and the second pen driving signal (PD2) is used to detect an additional input related to an additional function of the stylus pen and wherein the second pen driving signal (PD2) has three states so as to increase a transmission amount of information about the additional input, each of the three states represented by a respective one of: a first state signal ("0"), including a plurality of pulses having a same phase as the touch driving signal (TS); a second state signal ("1") including a plurality of pulses having a phase opposite the touch driving signal (TS); and a third state signal ("Passive") corresponding to a passive state of the second pen driving signal. wherein the touch driving device is configured to generate a touch driving signal (TS) during the touch driving period (TP), apply the touch driving signal (TS) to a touch screen (TSP), sense a first pen driving signal (PD1) applied to the touch screen (TSP) from a stylus pen in a first period (SS1) of the touch driving period (TP), and sense a second pen driving signal (PD2) applied to the touch screen (TSP) from the stylus pen in a second period (SS2) of the touch driving period (TP), wherein the first pen driving signal (PD1) and the second pen driving signal (PD2) are synchronized with the touch driving signal (TS), wherein the first pen driving signal (PD1) is used to detect an active stylus pen touch input, and the second pen driving signal (PD2) is used to detect an additional input related to an additional function of the stylus pen and wherein the second pen driving signal (PD2) has three states so as to increase a transmission amount of information about the additional input, each of the three states represented by a respective one of: a first state signal ("0"), including a plurality of pulses having a same phase as the touch driving signal (TS); a second state signal ("1") including a plurality of pulses having a phase opposite the touch driving signal (TS); and a third state signal ("Passive") corresponding to a passive state of the second pen driving signal. a first state signal ("0"), including a plurality of pulses having a same phase as the touch driving signal (TS); a second state signal ("1") including a plurality of pulses having a phase opposite the touch driving signal (TS); and a third state signal ("Passive") corresponding to a passive state of the second pen driving signal. <EOS>