LTC3703-5 Linear Technology, LTC3703-5 Datasheet - Page 29

• Manufacturer Part Number: LTC3703-5
• Description: 60V Synchronous Switching Regulator Controller
• Manufacturer: Linear Technology

APPLICATIO S I FOR ATIO
5. Place the small-signal components away from high
frequency switching nodes (BOOST, SW, TG, and BG). In
the layout shown in Figure 20, all the small signal compo-
nents have been placed on one side of the IC and all of the
power components have been placed on the other. This
also helps keep the signal ground and power ground
isolated.
6. A separate decoupling capacitor for the supply, V
useful with an RC filter between the DRV
pin to filter any noise injected by the drivers. Connect this
capacitor close to the IC, between the V
and keep the ground side of the V
ground) isolated from the ground side of the DRV
capacitor (power ground).
C
R
U
C2
C2
C
C3
R1
R2
R
U
C1
C
C1
R
R
C
MAX
SET
W
SS
CC
Figure 20. LTC3703-5 Buck Converter Suggested Layout
1
2
3
4
5
6
7
8
CC
capacitor (signal
CC
MODE/SYNC
FSET
COMP
FB
I
INV
RUN/SS
GND
MAX
supply and V
LTC3703-5
and GND pins
U
BGRTN
BOOST
DRV
V CC
SW
V
BG
TG
CC
IN
CC
16
15
14
13
12
11
10
9
, is
CC
CC
C
X5R
VCC
7. For optimum load regulation and true remote sensing,
the top of the output resistor divider should connect
independently to the top of the output capacitor (Kelvin
connection), staying away from any high dV/dt traces.
Place the divider resistors near the LTC3703-5 in order to
keep the high impedance FB node short.
8. For applications with multiple switching power convert-
ers connected to the same input supply, make sure that the
input filter capacitor for the LTC3703-5 is not shared with
other converters. AC input current from another converter
could cause substantial input voltage ripple, and this could
interfere with the operation of the LTC3703-5. A few
inches of PC trace or wire (L 100nH) between C
LTC3703-5 and the actual source V
to prevent input noise interference problems.
V
CC
C
X5R
R
DRVCC
F
D
C
M2
B
M1
B
V
IN
D1
+
C
IN
L1
C
OUT
+
www.DataSheet4U.com
IN
37035 F18
LTC3703-5
should be sufficient
V
OUT
+
–
IN
29
of the
37035f