Datasheet

27
LTC1628-SYNC
1628syncfa
signal ground. The R2 and R4 connections should not be
along the high current input feeds from the input
capacitor(s).
4. Are the SENSE
–
and SENSE
+
leads routed together
with minimum PC trace spacing? The filter capacitor
between SENSE
+
and SENSE
–
should be as close as
possible to the IC. Ensure accurate current sensing with
Kelvin connections at the SENSE resistor.
5. Is the INTV
CC
decoupling capacitor connected close to
the IC, between
the INTV
CC
and the power ground pins?
This capacitor carries the MOSFET drivers current peaks.
An additional 1µF ceramic capacitor placed immediately
next to the INTV
CC
and PGND pins can help improve noise
performance substantially.
6. Keep the switching nodes (SW1, SW2), top gate nodes
(TG1, TG2), and boost nodes (BOOST1, BOOST2) away
from sensitive small-signal nodes, especially from the
opposites channel’s voltage and current sensing feed-
back pins. All of these nodes have very large and fast
moving signals and therefore should be kept on the
“output side” of the LTC1628-SYNC and occupy minimum
PC trace area.
APPLICATIO S I FOR ATIO
WUUU
Figure 11. Branch Current Waveforms
R
L1
D1
L1
SW1
R
SENSE1
V
OUT1
C
OUT1
+
V
IN
C
IN
R
IN
+
R
L2
D2
BOLD LINES INDICATE
HIGH, SWITCHING
CURRENT LINES.
KEEP LINES TO A
MINIMUM LENGTH.
L2
SW2
1628 F11
R
SENSE2
V
OUT2
C
OUT2
+