Datasheet

Current Calculations
OUT (max)
OUT (max)
OUT
P
I
V
=
(8)
350
0 9
390
OUT (max)
W
I . A
V
= @
(9)
OUT (max)
IN _ RMS (max)
IN (min)
P
I
V PFh
=
(10)
350
4 52
0 92 85 0 99
IN _ RMS (max)
W
I . A
. V .
= =
´ ´
(11)
2
IN _ PEAK (max) IN _ RMS(max)
I I=
(12)
2 4 52 6 39
IN _ PEAK (max)
I . A . A= ´ =
(13)
2
IN _ PEAK (max)
IN _ AVG(max)
I
I
p
=
(14)
2 6 39
4 07
IN _ AVG(max)
. A
I . A
p
´
= =
(15)
Bridge Rectifier
2
BRIDGE F _ BRIDGE IN _ AVG(max)
P V I=
(16)
2 0 95 4 07 7 73
BRIDGE
P . V . A . W= ´ ´ =
(17)
UCC28019A
www.ti.com
.................................................................................................................................................. SLUS828B DECEMBER 2008 REVISED APRIL 2009
First, determine the maximum average output current, I
OUT(max)
:
The maximum input RMS line current, I
IN_RMS(max)
, is calculated using the parameters from Table 1 and the
efficiency and power factor initial assumptions:
Based upon the calculated RMS value, the maximum peak input current, I
IN_PEAK(max)
, and the maximum average
input current, I
IN_AVG(max)
, assuming the waveform is sinusoidal, can be determined.
Assuming a forward voltage drop, V
F_BRIDGE
, of 0.95 V across the rectifier diodes, BR1, the power loss in the
input bridge, P
BRIDGE
, can be calculated:
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