Datasheet

LT3579/LT3579-1
8
35791fa
For more information www.linear.com/LT3579
BLOCK DIAGRAM
Figure 1. Block Diagram
FREQUENCY
FOLDBACK
RAMP
GENERATOR
COMPARATOR
DRIVER
DISABLE
SS
V
C
R
FAULT
R
GATE
14.6k
14.6k
SR1
A3
SYNC CLKOUT
÷N
SS
SHDN
C
OUT1
SW1
SW2
FB
15.4m
R
S
12m
GND
R
T
RT
R
C
C
C
V
C
DRIVER
V
IN
C
IN
SYNC
BLOCK
UVLO
R
S
Q
35791 BD
–
+
A4
Q2
+
–
TD ~ 30ns
VBE • 0.9
–
+
–
+
1.17V
45mV
FB
∑
ADJUSTABLE
OSCILLATOR
–
+
–
+
A1
C
SS
1.33V
+
–
+
–
+
–
250k
2.1V
1.8V
50mV
SOFT-
START
STARTUP
& FAULT
LOGIC
C
OUT
V
OUT
V
IN
M
1
L1
GATE
OPTIONAL
FAULT
933µA
– + + – + –
+
–
+
–
+
–
DIE TEMP
165°C
V
IN
750mV
SW1
I
SW1
42V (MIN)
42V (MIN)
3.4A (MIN)
SW2
–
+
A2
1.215V
REFERENCE
16.2V
D1
R
FB
Q1
**
**
** SW OVERVOLTAGE PROTECTION IS NOT GUARANTEED TO PROTECT THE LT3579/LT3579-1 DURING SW OVERVOLTAGE EVENTS.