EXT
SWITCH
V
DD
R2
D1
+
C1
Q1
R10
D4
D3
1
Q3
D5
2
P
3
D2
R1
R9
U3
1
2
R3
3
4
C2
V
DD
MODE
TEST
SYNC
GATE
V
SS
OVC
SENS/
8
7
6
5
C4
R5
LS7636
R4
R6
SENSE C3
SWITCH
3
2
Q4
1
3
4
Q2
1
R7
R8
TRANSFORMER
2
LOAD
N
FIGURE 4. Reverse Phase Dimmer (Option 1)
C1 = 100uF
C2 = 0.0047uF
C3 = 0.047uF
C4 = 0.1uF
R1 = 150kΩ
*
R1 = 270kΩ, 1/2W
R2 = 390Ω
R3 = 39kΩ
R4 = 1.5MΩ
R5 = 10kΩ
R6 = 150kΩ
D4 = 1N4004
*
R6 = 270kΩ
D5 = 1N4004
R7 = 47kΩ
Q1 = MJE340 (or equivalent)
*
R7 = 91kΩ
Q2 = Liteon LTV354T (or equivalent)
R8 = 47kΩ
Q3 = IRF630 (Typical)
*
R8 = 91kΩ
*
Q3 = IRF730 (Typical)
R9 = 0.25Ω, 1W (For
1 Amp RMS Max)
Q4 = IRF630 (Typical)
*
Q4 = IRF730 (Typical)
R10 = 4.3kΩ, 1/2W
D1 = 12V, 1/2W, 5%
D2 = 5.6V, 1/4W, 10%
All Resistors 1/4W, All Capacitors 25V unless otherwise specified
D3 = 1N4004
* = Component change for 220VAC
7636-041709-5
LSI [ LSI COMPUTER SYSTEMS ]
