RT9241A RICHTEK [Richtek Technology Corporation], RT9241A Datasheet - Page 15

• Manufacturer Part Number: RT9241A
• Description: Two-Phase DC/DC Controller for CPU Core Power Supply
• Manufacturer: RICHTEK [Richtek Technology Corporation]

Layout Guide
Layout Guide
Place the high-power switching components first, and
separate them from sensitive nodes.
1.Most critical path: the current sense circuit is the most
No Kelvin sense, no guarantee for stable operation!
DS9241AB-05 March 2007
sensitive part of the converter. The current sense
resistors tied to ISP1,2 and ISN1,2, should be located
not more than 0.5 inch from the IC and away from the
noise switching nodes. The PCB trace of sense nodes
should be parallel and as short as possible. Kelvin
connection of the sense component (additional sense
resistor or MOSFET R
stable current sensing.
R
IN
V
V
IN
DS(ON)
C
IN
) ensures the accurate
Figure.7 Power Stage Ripple Current Path
SW1
SW2
Switching ripple current path:
2.MOSFET driver should be close to MOSFET
4.The compensation, bypass and other function setting
a.Input capacitor to high side MOSFET
b.Low side MOSFET to output capacitor
c.The return path of input and output capacitor
d.Separate the power and signal GND
e.The switching nodes (the connection node of high/
f.Reduce parasitic R, L by minimum length, enough
components should be near the IC and away from the
noisy power path.
low side MOSFET and inductor) is the most noisy
points. Keep them away from sensitive small-signal
node.
copper thickness and avoiding of via.
L2
L1
V
OUT
C
OUT
RT9241A/B
R
L
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