DESCRIPTION:

The LS7338 is a monolithic MOS integrated circuit designed to turn a triac On and Off in a Power Switch for Incandescent Lighting. Activation of SENSE or SLAVE inputs turns the triac On and starts 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. When Time-out occurs, the power delivered by the triac is stepped down by 31 and then slowly reduced to Off over a fixed period of time.

FEATURES:

• Phase-Lock Loop Synchronization allows use in Wall Switch Applications.

• Operation automatically sequences from Timed-On to Delayed-Off to Off.

• On-Timer programmable with external R-C.

• Transition from Timed-On to Delayed Off indicated by 31 drop in Delivered Power.

• Delayed-Off period denoted by Dim-to-Off operation. (See Note 1)

• Control input initiates Operating Sequence and can override Automatic Sequencing.

• 50/60Hz Line Frequency.

• +12V to +18V Operation (VSS - VDD).

• LS7338 (DIP); LS7338-S (SOIC) - See Figure 1

APPLICATIONS:

• WALL SWITCH for incandescent lighting in garage, corridor, staircase, child’s bedroom, teenage study area.

• IN-LINE SWITCH for table lamps.