Datasheet

LTC3859
13
3859fa
FUNCTIONAL DIAGRAM
3859 BD
SWITCHING
LOGIC
INTV
CC
V
IN1,2
D
B
C
B
BOOST
TG
SW
BG
PGND
SENSE
+
SENSE
–
C
IN
D
C
OUT
INTV
CC
L
R
SENSE
TOP BOT
DROPOUT
DET
SQ
R Q
BOT
TOPON
SHDN
+ –
SLEEP
+ –
+ –
+
–
+
–
ICMP
IR
2.8V
0.65V
SLOPE COMP
V
FB
I
TH
3mV
0.80V TRACK/SS 0.88V
+ – + – –
TRACK/SS
OV
C
C2
RC
C
C
RUN
C
SS
FOLDBACK
SHDN
R
ST
2(V
FB
)
SHDN
6µA CH1 0.5µA CH2
11V
PFD
VCO
C
LP
CLK2 CLK1
SYNC
DET
20µA
100k
R
A
R
B
LDO
EN
LDO
EN
+ –
4.7V
5.4V 5.4V
INTV
CC
SGND
EXTV
CC
V
BIAS
FREQ
PGOOD1
+ – + –
0.88V 0.72V
V
FB1
EA
BUCK CHANNELS 1 AND 2
1µA
V
OUT1,2