●DESCRIPTION:
●LS7231 through LS7234 are a series of monolithic, MOS integrated circuits designed for the control of brightness of incandescent lamps. The outputs of these ICs control the brightness of a lamp by controlling the firing angle of a triac connected in series with the lamp. All internal timings are synchronized with the line frequency by means of a built-in phase-lock loop circuit. The output occurs once every half-cycle of the line frequency. Within the half cycle, the output can be positioned anywhere between 158˚conduction angle for maximum brightness and 41˚ conduction angle for minimum brightness in relation to the AC line frequency. The positioning of the output is controlled by applying a low level at the SENS input or a high level at the EXT input.
●FEATURES:
●• Phase-lock loop synchronization allows use in Wall Switch applications.
●• Provides brightness control of incandescent lamps with touch plates or mechanical switches.
●• Controls the "duty cycle" from 23% to 88%
● (conduction angles for AC half-cycles between 41˚ and 158˚, respectively.)
●• Operates at 50Hz/60Hz line frequency.
●• Extension input for remote activation.
●• Input for slow dimming.
●• +12V to +18V DC Power Supply voltage. (VSS - VDD)
●• LS7231 to LS7234 (DIP) - See Figure 1
● LS7231-S to LS7234-S (SOIC)
●APPLICATIONS:
●1\. Foot-Switch Dimmer for large floor lamps.
●2\. Hand-Switch Dimmer for end-table lamps.
