VIPER15 STMicroelectronics, VIPER15 Datasheet - Page 30

• Manufacturer Part Number: VIPER15
• Description: VIPerPlus family: quasi-resonant high performance off line high voltage converter
• Manufacturer: STMicroelectronics

Operation description
30/40
Equation 11
The R
page
The C
Equation 8 on page 29
considered instead of C
satisfy, in all case, the loop stability and the enough OLP delay time alike.
Figure 34. FB pin configuration (option 1)
Figure 35. FB pin configuration (option 2)
8.
FB1
FB(DYN)
capacitor fixes the OLP delay and usually C
is the dynamic resistance seen by the FB pin and reported on
Rfb1
Cfb1
FB
can be still used to calculate the OLP delay time but C
. Using the alternative compensation network, the designer can
Cfb
Cfb
f
PFB
Doc ID 15455 Rev 5
1
=
2
⋅
⋅ π
CONTROL
CONTROL
PWM
PWM
C
FB
REFERENCES
REFERENCES
BURST-MODE
BURST-MODE
1
⋅
(
R
1
FB
1
4.8V
4.8V
+
FB1
R
OLP comparator
FB
OLP comparator
(
results much higher than C
DYN
BURST-MODE
BURST-MODE
PWM
PWM
From sense FET
+
+
From sense FET
+
+
-
-
-
-
LOGIC
LOGIC
)
)
To disable logic
To disable logic
To PWM Logic
To PWM Logic
BURST
BURST
Table 8 on
FB1
has to be
VIPER15
FB
. The