The LS7339 and LS7340 are monolithic MOS integrated circuits designed to turn a triac On and Off in a Power Switch for AC loads. Activation of the ON input will always turn the triac On and start a Timer. The triac remains On for the duration of the Timer which is controlled by an external R-C connected to the OSCILLATOR input. Activation of the OFF input will always turn the triac Off. The two ICs differ only in the width of the TRIG pulse used to trigger the triac. (See I/O Description, Pin 4.)