lt3742 Linear Technology Corporation, lt3742 Datasheet - Page 7

• Manufacturer Part Number: lt3742
• Description: Dual, 2-phase Step-down Switching Controller
• Manufacturer: Linear Technology Corporation

BLOCK DIAGRAM
PGOOD
SHDN
V
IN
25
2
3
GND
V
UVLO
RUN/SS
PG
IN
LT3742 CONTROLLER 1 AND 2
1.25V
COMPARATOR
3μA
1μA
TO ENABLE
UVLO
+
–
≈0.5V
RUN/SS1
RUN/SS2
UNDERVOLTAGE
TO
SS
LOCKOUT
COMPARATOR
COMPARATOR
ENABLE
–
+
+
PWM
R
S
ENABLE
Q
500kHz SLAVE
PHASE SYNC
SHUTDOWN
OSCILLATOR
+
–
THERMAL
Σ
COMPARATORS
BOOST REGULATOR
POWER GOOD
GATE DRIVE BIAS
1MHz MASTER
INTERNAL
OSCILLATOR
SUPPLY
V
REF
AMPLIFIER
AMPLIFIER
CURRENT
ERROR
SENSE
–
+
–
+
1.25V
0.86V
0.80V
0.74V
+
–
–
+
+
DRIVER
0.86V
0.74V
GATE
0.80V
BIAS
FB
DC/DC CONTROLLERS
BIAS
PHASE SYNC FOR
D
Q
ENABLE
SENSE
SENSE
Q
SWB
BIAS
SW
V
FB
G
+
–
C
5
4
3742 BD1
V
V
IN
IN
LT3742
7
3742f
V
OUT