Texas Instruments LM3445 Evaluation Board LM3445-120VFLBK/NOPB LM3445-120VFLBK/NOPB Benutzerhandbuch
Produktcode
LM3445-120VFLBK/NOPB
R
FLTR1
R
SNS
PWM
I-LIM
1.25V
I
SNS
ASNS
PGND
FLTR1
FLTR2
DIM
DIM DECODER
4.5V
Tri-State
50k
333k
C
FLTR2
C
FLTR1
1k
RAMP GEN.
5.5 kHz
3V
1V
1V
750 mV
110 ns
LEADING EDGE BLANKING
1V
Nearly a constant on-
time as the line varies
The PWM reference increases
as the line voltage increases.
As line voltage increases, the voltage across the
inductor increases, and the peak current increases.
1V
D x LED Current
Circuit Analysis and Explanations
Figure 36. Typical Operation of FLTR2 Pin
27
SNVA429C – August 2010 – Revised May 2013
AN-2034 LM3445 -120VAC, 8W Isolated Flyback LED Driver
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