VIPER53-E STMicroelectronics, VIPER53-E Datasheet - Page 21

• Manufacturer Part Number: VIPER53-E
• Description: Fixed frequency off line converter
• Manufacturer: STMicroelectronics

VIPer53 - E
Note:
Equation 3
Where Ip(V
voltage of V
The power point PSTBY where the converter is going into burst mode does not depend on
the input voltage.
The standby frequency F
Equation 4
The ratio between the nominal and standby switching frequencies can be as high as 4,
depending on the Lp value and input voltage.
Figure 20. Standby mode implementation
COMPbl
COMPbl
Minimum
turn on
350ns
P
600ns
ton
P
P
STBY
RST
IN
2
(1V).
) is the peak Power MOSFET current corresponding to a compensation
V
V
COMPsd
COMPoff
3
SWstby
P
STBY
F
SWstby
is given by:
P
3
=
SWstby
1
-- -
2
2
V
F
COMPbl
SWnom
=
P
---------------- -
P
STBY
RST
Ip
1
2
F
V
F
SWnom
SWnom
COMPbl
1
2
Lp
V
COMP
F
SW
Standby mode
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