LM3444-230VAC NSC [National Semiconductor], LM3444-230VAC Datasheet - Page 10

• Manufacturer Part Number: LM3444-230VAC
• Description: 8W Isolated Flyback LED Driver Industrial and Commercial Lighting
• Manufacturer: NSC [National Semiconductor]

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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 achieve desired LED current by interpolating R21 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
PCB Layout
Ch1: FILTER Voltage (200 mV/div); ISNS Voltage
FILTER (Pin-5) and ISNS (Pin-7) Voltage
(V
IN
=230V
(200 mV/div); Time (4 µs/div)
RMS
, 6 LEDs, I
LED
= 350mA
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Top Layer
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