NCP5222 ON Semiconductor, NCP5222 Datasheet - Page 16

• Manufacturer Part Number: NCP5222
• Description: High Performance Dual-channel / Two-phase Synchronous Buck Controller For Notebook Power System
• Manufacturer: ON Semiconductor

turned off. The fault remains set until the system has
shutdown and re−applied V
has toggled states.
Thermal Protection
protect the device itself from overheating when the die
temperature exceeds 150°C. After the thermal protection is
triggered, the fault state can be ended by re−applying V
or EN when the die temperature drops down below 125°C.
Layout Guidelines
stage components for dual−channel configuration and
two−phase configuration, respectively.
on, the voltage difference across the sharing−switch will
cause a current flow through it, which is used to balance
The NCP5222 has a thermal shutdown protection to
Figures 11 and 12 show exemplary layout of the power
In the two−phase mode, after the sharing switch is turned
CC
and/or the enable signal EN
Figure 11. Layout Guidelines in Dual−Channel Mode
http://onsemi.com
CC
16
power delivery between the two phases. The smaller R
of the sharing switch (R
and the smaller output voltage deviation in V
the current through the sharing switch can be calculated by
I
R
two output sensing points. So that too large R
wastes R
power sharing capability and enlarges V
voltage regulation, the V
designed like remote sensing. In the meantime, to fully use
the sharing switch for the current sharing operation and
reduce V
points V
possible.
ssh
on_ssh
In a real application, to make sure the CH1 has perfect
= (V
+ R
O1
O2
O2
DS(on)
pcb
deviation, the distance between the two sensing
and V
− V
, and R
of the sharing switch, and thus reduces the
O1
O2
) / R
pcb
should be arranged to be as close as
on_ssh
on_effective
is the copper resistance between the
O1
sensing point and AGND can be
), the better the current balance
, in which R
O2
deviation.
pcb
O2
on_effective
effectively
. Actually,
DS(on)
=