Datasheet

OUT
LINE
OUT
2 2 2 2
OUT OUT _ MIN
P
1
300 W 1
2
2
f
0.92 47Hz
C 156 F
V (V ) 390 V (252 V)
h
³ = » m
- -
OUT
C 200 F= m
OUT
RIPPLE
OUT LINE OUT
2 P
1 2 300 W
V 14 Vppk
V 4 f C 0.92 390 V 4 47Hz 200 F
´
´
= = »
h ´ p´ ´ ´ ´ p ´ ´ m
OUT
COUT _100Hz
OUT
P
300 W
I 0.591 Arms
V 2 390 V 0.92 2
= = =
´ h´ ´ ´
( )
2
2
IN _MIN
OUT
COUT _ HF COUT _100Hz
IN _MIN OUT
4 2V
P 2 2
I I
2 V 9 V
æ ö
ç ÷
= -
ç ÷
´ h´ p
ç ÷
è ø
( )
2
2
COUT _ HF
300 W 2 2 4 2 85 V
I 0.591A 0.966 Arms
2 0.92 85 V 9 390 V
æ ö
´ ´
ç ÷
= - »
ç ÷
´ ´ p´
è ø
UCC28063
www.ti.com SLUSAO7 –SEPTEMBER 2011
Output Capacitor Selection
The output capacitor (C
OUT
) is selected based on holdup requirements, as shown in Equation 31.
(31)
Two 100-μF capacitors were used in parallel for the output capacitor.
(32)
For this size capacitor, the low-frequency peak-to-peak output voltage ripple (V
RIPPLE
) is approximately 14 V, as
shown in Equation 33:
(33)
In addition to holdup requirements, a capacitor must be selected so that it can withstand the low-frequency RMS
current (I
COUT_100Hz
) and the high-frequency RMS current (I
COUT_HF
); see Equation 34 to Equation 36.
High-voltage electrolytic capacitors generally have both a low- and a high-frequency RMS current ratings on the
product data sheets.
(34)
(35)
(36)
Copyright © 2011, Texas Instruments Incorporated Submit Documentation Feedback 37
Product Folder Link(s): UCC28063