rt9237 ETC-unknow, rt9237 Datasheet - Page 12

• Manufacturer Part Number: rt9237
• Description: Multi-phase Dc/dc Controller Core Power Supply
• Manufacturer: ETC-unknow

RT9237
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
No Kelvin sense, no guarantee
for stable operation!
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12
the most sensitive part of the converter. The
current sense resistors tied to ISP1,2,3,4 and
ISN1,2,3,4 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
MOSFET R
current sensing.
DS(ON)
(additional
R
IN
) ensures the accurate stable
V
V
C
IN
IN
sense
Fig.7 Power Stage Ripple Current Path
resistor
SW1
SW2
Preliminary
or
L1
L2
2. Switching ripple current path:
3. MOSFET driver should be close to MOSFET
4. The compensation, bypass and other function
setting components should be near the IC and
away from the noisy power path.
e. The switching nodes(the connection node of
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
f. Reduce parasitic R, L by minimum length,
enough copper thickness and avoiding of via.
high/low side MOSFET and inductor) is the
most noisy points. Keep them away from
sensitive small-signal node.
V
C
OUT
OUT
R
DS9237-00 January 2002
L