Datasheet

LT3504
8
3504fa
For more information www.linear.com/LT3504
block DiagraM
3504 BD
V
IN
Σ
S
R NQ
S
R NQ
Σ
SYNC
DETECT
CLK1 CLK2
OSC
FREQUENCY
TO CURRENT
TO CH2, CH4
STARTUP/SHUTDOWN
THERMAL SHUTDOWN
0.4V
1.3µA
1.44V
ON
REF
PRECISION UVLO
V
IN
EN/UVLO
LOCK
1SHOT
SLOPE
SLOPE
1SHOT
TO CH3
SKY
4.85V
BOOST ERROR AMP
0.7V
BOOST SWITCH AND DRIVE
SW5 SW1
DA1
PG
SKY
V
IN
PGOOD
OUT1
COMPARATORS FROM OTHER CHANNELS
FB1
0.72VCURRENT LIMIT FOLDBACK
0.8V
0.7V
SKYBAD
0.8V
BOOST REGULATOR
Q5
D5
Q1
SWITCH AND DRIVE
ONE OF THE FOUR BUCK REGULATORS SHOWN
POWER GOOD LOGIC
RT/SYNC
RUN/SS1 FB1 GND
2.2V
0.1V
4.5V
RAMP
1µA
SKYBAD
SKY
V
IN
SKYBAD
0
1
+
–