User manual

Output Power vs. Line Voltage
Original Circuit
180 190 200 210 220 230 240 250 260
2
3
4
5
6
7
8
9
10
11
12
OUTPUT POWER (W)
LINE VOLTAGE (V
RMS
)
10 LEDs
8 LEDs
4 LEDs
6 LEDs
30126913
Output Power vs. Line Voltage
Modified Circuits
180 190 200 210 220 230 240 250 260
0.0
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
25.0
OUTPUT POWER (W)
INPUT VOLTAGE (V
RMS
)
Mod C (10 LEDs)
Mod B (8 LEDs)
Original (6 LEDs)
Mod A (4 LEDs)
30126917
Line Voltage and Line Current
(V
IN
= 230V
RMS
, 6 LEDs, I
LED
= 350mA)
30126918
Ch1: Line Voltage (100 V/div); Ch3: Line Current
(20 mA/div); Time (4 ms/div)
Output Voltage and LED Current
(V
IN
= 230V
RMS
, 6 LEDs, I
LED
= 350mA)
30126920
Ch1: Output Voltage (10 V/div); Ch3: LED Current
(100 mA/div); Time (4 ms/div)
Power MOSFET Drain and ISNS (Pin-7) Voltage
(V
IN
= 230V
RMS
, 6 LEDs, I
LED
= 350mA)
30126921
Ch1: Drain Voltage (100V/div); Ch4: ISNS Voltage
(500 mV/div); Time (4 µs/div)
FLTR2 (Pin-5) and ISNS (Pin-7) Voltage
(V
IN
=230V
RMS
, 6 LEDs, I
LED
= 350mA
30126922
Ch1: FLTR2 Voltage (200 mV/div); ISNS Voltage
(200 mV/div); Time (4 µs/div)
Note 1: Original Circuit (6 LEDs operating at 350mA): R21 = 2.7Ω; Modification A (10 LEDs operating at 375mA): R21 = 1.8Ω; Modification B (8 LEDs operating
at 350mA): R21 = 2.2Ω; Modification C (4 LEDs operating at 315mA): R21 = 3.9Ω
Note 2: The output power can be varied to acheive desired LED current by interpolating R14 values between the maximum of 3.9 Ω and minimum of 1.8 Ω
Note 3: The maximum output voltage is clamped to 36 V. For operating LED string voltage > 36 V, replace D6 with suitable alternative
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