LSI Computer Systems LS7339
The LS7339 and LS7340 are monolithic MOS integrated circuits designed to turn a triac On and Off in a Power Switch for AC loads. The triac remains On for the duration of the Timer which is controlled by an external R-C connected to the OSCILLATOR input. The two ICs differ only in the width of the TRIG pulse used to trigger the triac.| Part No. | LS7339 |
|---|---|
| Datasheet | LS7339 Download |
| Manufacturer |  LSI Computer Systems |
| Description | AUTO SHUT-OFF AC POWER SWITCH |
| Buy | Stock & Price |
FEATURES
:● Phase-Lock Loop Synchronization allows use in Wall Switch
APPLICATIONS
.● PLL accuracy delivers Pure AC Power.
● Timer programmable with external R-C.
● ON input switches AC Power On and starts Timer.
● OFF input switches AC Power Off.
● 50/60Hz Line Frequency.
● +12V to +18V Operation (VSS - VDD).
● LS7339, LS7340 ( DIP) - See Figure 1 LS7339-S, LS7340-S (SOIC)
APPLICATIONS
:● AUTO SHUT-OFF TIMER for appliances such as coffee pots, curling irons, hair curlers, electric blankets, hand dryers.
● TIMED-ON WALL SWITCH for incandescent lighting and heat lamps.
DESCRIPTION
: Activation of the ON input will always turn the triac On and start a Timer. Activation of the OFF input will always turn the triac Off. (See I/ODESCRIPTION
, Pin 4.) In a typical application (Figure 5), the output of the LS7339 drives the gate of a triac in series with the load. Because the LS7339 is accurately synchronized to the line frequency with a phase-lock loop, the power delivered by the triac to the load is pure AC, allowing use with inductive loads such as motors and transformers.
