FIGURE 4. LS7635 TRIG, Ø vs TOUCH (SENS OR EXT)
T
S1
SENS
SHORT
SHORT
LONG
LONG
LONG
LONG
SHORT
LONG
SHORT
T
S2
Ø
MODE Ø
150º
100º
50º
OFF
SLOPE = S
S
342ms
A0
A2
SLOPE = S
AA
A0
SLOPE = S
BA
B2
A1
B1
B2
A2
B2
A2
MEMORY
MEMORY
Ø
MODE 1
150º
100º
50º
OFF
A1
B1 B2
A2
REVERSE
A1
A2
B1
B2
REVERSE
150º
100º
50º
OFF
B2
Ø
MODE 2
A0
A0
A0
A0
A2
B2
A2
FIGURE 5. A Typical Halogen Lamp Dimmer Wall Switch
P
**C6
MT1
G
P
SEE NOTE 2
R8
C5
R3
R7
EXTN
ELECTRONIC
EXTENSION
(FIG. 7)
**R9
MT2
T
Z
+
C4
R5
-
SEE NOTE 3
TOUCH
PLATE
NOTES
R6
115VAC
OR
220VAC
L
C1
C2
R1
V
DD
D1
8
TRIG
7
V
SS
6
EXT
5
SENS
LS7634 / LS7635
MODE TEST SYNC
R2
1
2
3
4
R4
SEE
NOTE 4
LAMP
C3
N
1.
All circuits connected by broken lines are optional.
2.
C5 is used only with electronic extension
and R7 is used only with mechanical switch.
3.
Connection between Pin 6 & Pin 7 should
be broken when EXT is used.
4.
Magnetic transformer should have thermal protection.
5.
Some electronic transformers may require larger
values of C2, sensitive gate triacs and snubber
networks. C2 values may have to be adjusted to be as
high as 0.47uF for 115VAC and 0.33uF for 220VAC.
The sensitive gate triacs are chosen for their low
holding current. Typical triacs are L4004L6 and L6004L6
for 115VAC and 220VAC applications, respectively.
**C6-R9 is the snubber network: C6 = 0.1uF, 200V,
R9 = 1k Ohm, 1/2W (115VAC); C6 = 0.05uF, 400V,
R9 = 1k Ohm, 1W (220VAC)
C1 = 0.15µF, 200V
*
C1 = 0.15µF, 400V
C2 = 0.22µF, 200V
*
C2 = 0.15µF, 400V
C3 = 0.002µF, 10V
*
Component change for 220VAC
**
Snubber Network (See Note 5)
FIGURE 6.
C4 = 100µF, 10V
C5 = 0.1µF, 10V
R1 = 270Ω, 1/2W
*
R1 = 1kΩ, 1W
R2 = 680kΩ, 1/4W
*
R2 = 1.5MΩ, 1/4W
R3 = 1.5MΩ, 1/4W
*
R4 = 1MΩ to 5MΩ, 1/4W
(Select for Sensitivity)
R5, R6 = 2.7MΩ, 1/4W
R5, R6 = 4.7MΩ, 1/4W
R7 = 150kΩ, 1/4W
R8 = 62Ω, 1/4W
D1 = 1N4148
Z = 5.6V, 1W (Zener)
T = Q4004L4 Typical Triac
(1)
*
T = Q5003L4 Typical Triac
(1)
L = 100µH (RFI Filter)
*
L = 200µH (RFI Filter)
(1)
For loads greater than 6A,
use an alternistor
ELECTRONIC EXTENSION
MPS8599
EXT
10kΩ
TOUCH PLATE
200kΩ
*R
= 2M
Ω
for 115VAC
*R
= 3.6M
Ω
for 220VAC
All Resistors 1/4W
IN914
*R
*R
.
APPLICATION EXAMPLE:
A typical implementation of the light dimmer circuit is shown in Fig. 5.
Here the brightness of the lamp is set by touching the touch plate.
The function of different components are as follows:
• The 5V DC supply for the chip is provided by Z, D1, R1, C2 and C4.
• R2 and C3 generate the filtered signal for the SYNC input
AC phase synchronization.
• R3 and C5 act as a filter circuit for the electronic extension.
If extensions are not used, the EXT input (Pin 6) should be
tied to Vss (Pin 7).
• R4, R5 and R6 set up the sensitivity of the SENS input.
• R8 provides current limiting and isolation between the chip
output and the triac gate.
• C1 and L are RFI filter circuits.
P
EXTENSIONS:
All switching and dimming functions can be
implemented by utilizing the EXT input. Use a pushbutton or
the electronic switch in conjunction with a Touch Plate as
shown in Figure 6. When the plate is touched, a logic high
level is generated at the EXT input of the IC for both half-
cycles of the line frequency. (See Figure 5)
7634/7635-090606-4
LSI [ LSI COMPUTER SYSTEMS ]
