LTC3727-1 Linear Technology, LTC3727-1 Datasheet - Page 26

• Manufacturer Part Number: LTC3727-1
• Description: 2-Phase Synchronous Step-Down Switching Regulators
• Manufacturer: Linear Technology

APPLICATIO S I FOR ATIO
LTC3727/LTC3727-1
2. Are the signal and power grounds kept separate? The
combined LTC3727 signal ground pin and the ground
return of C
terminals. The path formed by the top N-channel MOSFET,
Schottky diode and the C
leads and PC trace lengths. The output capacitor (–)
terminals should be connected as close as possible to the
(–) terminals of the input capacitor by placing the capaci-
tors next to each other and away from the Schottky loop
described above.
3. Do the LTC3727 V
nect to the (+) terminals of C
must be connected between the (+) terminal of C
signal ground. The R2 and R4 connections should not be
26
R1
R3
INTVCC
must return to the combined C
R2
R4
U
INTV
OSENSE
3.3V
CC
U
IN
f
IN
capacitor should have short
pins resistive dividers con-
10
11
12
13
14
Figure 10. LTC3727 Recommended Printed Circuit Layout Diagram
1
2
3
4
5
6
7
8
9
OUT
RUN/SS1
SENSE1
SENSE1
V
PLLFLTR
PLLIN
FCB
I
SGND
3.3V
I
V
SENSE2
SENSE2
TH1
TH2
OSENSE1
OSENSE2
? The resistive divider
W
OUT
LTC3727
+
–
–
+
RUN/SS2
BOOST1
BOOST2
PGOOD
EXTV
INTV
PGND
SW1
SW2
BG1
BG2
TG1
TG2
V
U
CC
CC
IN
OUT
28
27
26
25
24
23
22
21
20
19
18
17
16
15
OUT
and
(–)
along the high current input feeds from the input
capacitor(s).
4. Are the SENSE
with minimum PC trace spacing? The filter capacitor
between SENSE
possible to the IC. Ensure accurate current sensing with
Kelvin connections at the SENSE resistor.
5. Is the INTV
the IC, between the INTV
This capacitor carries the MOSFET drivers current peaks.
An additional 1 F ceramic capacitor placed immediately
next to the INTV
performance substantially.
R
PGOOD
PU
C
C
C
B1
B2
INTVCC
V
(<7V)
PULL-UP
CC
C
CC
V
VIN
R
decoupling capacitor connected close to
+
IN
M1
IN
M3
and PGND pins can help improve noise
–
and SENSE
and SENSE
M2
M4
CC
L1
C
L2
IN
and the power ground pins?
–
+
R
R
www.DataSheet4U.com
should be as close as
SENSE
SENSE
C
C
leads routed together
D1
OUT1
OUT2
D2
3727 F10
V
GND
V
OUT1
OUT2
3727f