VIPER53E-E STMicroelectronics, VIPER53E-E Datasheet - Page 17

• Manufacturer Part Number: VIPER53E-E
• Description: Fixed frequency off line converter
• Manufacturer: STMicroelectronics

VIPer53EDIP - E / VIPer53ESP - E
The lowest load gives another condition for stability: The frequency F
encounter the third order slope generated by the load pole, the R1-C1 network on the
COMP pin and the R2-C2 network at the level of the TL431 on secondary side. This
condition can be met by adjusting both C
The above formula gives a minimum value for C1. It can be then increased to provide a
natural soft start function as this capacitor is charged by the current I
with:
C
2
C
DocRev1
1
---------------------------------------------- -
6.3
---------------------------------- -
6.3
R
R L1 C OUT
P
L1
G
-------- - R
OUT1
1
R
O
4
G O
-------- - R 1
and C2 values:
R 4
C
OUT
1
=
2
V
------------------ -
R
R
2
2
OUT
L1
P
-------------------- -
P MAX
OU T1
P OU T1
-------------------- -
P
MAX
Regulation Loop Stability
COMP
BW1
must not
at start-up.
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