STMicroelectronics 19V - 90W Adapter with PFC for Laptop computers using the L6563H and L6699 EVL6699-90WADP EVL6699-90WADP Fiche De Données
Codes de produits
EVL6699-90WADP
L6699
Line sensing function
Doc ID 022835 Rev 2
31/38
Figure 22.
Line sensing function: internal block diagram and timing diagram
While the line undervoltage is active there is no switching activity, therefore the V
CC
voltage
(if not supplied by another source) continuously oscillates between the startup and the
UVLO thresholds, as shown in the timing diagram of
UVLO thresholds, as shown in the timing diagram of
.
The LINE pin, while the device is operating, is a high impedance input connected to high
value resistors, so it is prone to pick-up noise,. This might alter Vin
value resistors, so it is prone to pick-up noise,. This might alter Vin
OFF
or give rise to
undesired switch-off of the IC during ESD tests. It is possible to bypass the pin to ground
with a small film capacitor (e.g. 1-10 nF) to prevent any malfunctioning of this kind.
with a small film capacitor (e.g. 1-10 nF) to prevent any malfunctioning of this kind.
If the function is not used the pin can be pulled high by connecting it to V
CC
through a
resistor in the hundred k
Ω
.
!-V
(6
6IN/+
6CC
6IN
/.
6IN
/&&
,6'
(6'
6OUT
,).%
6
)
(93
T
T
T
T
T
T
T
,
6IN/+
(6
,).%
6CC
6
2
(
2
,