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AGC Touch Control Light Switch with Soft-Off (8 Pins)
LS7540-S, LS7540
Category: Lighting Controls
Status: In Production
Stock Availability: DIP, SOIC
All of our Standard Products are RoHS Compliant
For pricing and availability, you may contact us, or request a quote. Most of our standard parts are available for purchase on Digi-Key, and through our Distributors.
Features:
• Touch Sensitivity is independent of Touch Plate Size and Line-Plug Polarity
• If Off, a ‘Touch’ produces Max Intensity (On) instantaneously
• If On, a ‘Touch’ initiates intensity ramp-down (Soft-Off). Max intensity to Off ramp-down time is programmable by an external RC. The Soft-Off feature provides light for the User to exit the room. Ramp-down time = 0 if no RC is connected.
• Application of a ‘Touch’ during ramp-down causes the ramp-down to stop. Once stopped, a ‘Touch’ causes the ramp-down to Off to resume. Stopping and starting the ramp-down can be repeated as often as desired thus giving the User full control in setting the light intensity.
• Pushbutton control can be used instead of ‘Touch’.
• Applications include Wall Switches and Touch Control modules for small table lamps to large floor lamps
Description:
The LS7540 is a CMOS integrated circuit for controlling the brightness of incandescent lamps with momentary touch. When its TOUCH input is connected to a lamp body, the entire lamp turns into a touch plate. A built-in AGC circuit allows for a wide range of lamp sizes to be used, ranging from very small table lamps to very large floor lamps. The brightness is controlled by controlling the conduction angle of a triac in series with the lamp and triggered by the TRIG/ output. Between off and maximum, there are 124 steps of brightness levels, level zero being off and level 124 being maximum. The phase reference of the TRIG/ signal with respect to the AC line is maintained through the SYNC input.
Code
Package
Notes
P/N
RoHS Compliant Standard plastic DIP
1, 2, 3
P/N – S
RoHS Compliant Standard SOIC
1, 2, 3, 4
P/N – SW
RoHS Compliant Widebody SOIC option
1, 2, 3, 4
P/N – S14
RoHS Compliant 14-pin SOIC version of 8-pin part
1, 2, 3, 4
P/N – TS
RoHS Compliant TSSOP
1, 2, 3, 4
P/N – TS24
RoHS Compliant 24-pin TSSOP version of 20-pin part
1, 2, 3, 4
Example: LSxxxx-TS = the LSxxxx in the RoHS Compliant TSSOP package-type
Note 1: See Table for package body widths Note 2: Package outline drawings conform to JEDEC standards Note 3: Packages shipped in anti-static tubes Note 4: Tape and Reel option available. Contact factory for details
ADDITIONAL ORDERING OPTIONS: Probed Wafers (P/N-PW), Waffle Packed Die (P/N-WP)
Package Body Widths
# of Pins
P/N, -C, -CM mils
-S mils
-SW mils
-TS mils
8
300
150
–
–
14
300
150
–
173
16
300
150
300
173
18
300
300
–
–
20
300
300
–
173
24
600
300
–
173
28
600
300
–
173
38
–
–
–
173
40
600
–
–
–
48
–
–
–
240