lt3517 Linear Technology Corporation, lt3517 Datasheet - Page 7

• Manufacturer Part Number: lt3517
• Description: Full-featured Led Driver With 1.5a Switch Current
• Manufacturer: Linear Technology Corporation

BLOCK DIAGRAM
PV
IN
SHDN
CTRL
FB
V
SYNC
SS
R
C
T
1.01V
+
ISP
R
1V
SENSE
X10
1V
V
–
IN
ISN
–
+
+
+
–
10μA
CURRENT
SENSE
AMPLIFIER
A1
A2
–
+
1V
A5
+
+
–
A6
+
+
ADJUST
FREQ
SS
C
A3
IN
Figure 1. Buck Mode LED Driver
AMPLIFIER
Q2
ERROR
MOSFET DRIVER
2.5MHz TO 250kHz
V
TG
ISP
OSCILLATOR
GENERATOR
V
ISP
– 7V
RAMP
LED ARRAY
+
–
V
COMPARATOR
IN
A4
PWM
TGEN
R
S
Q
C
FILT
PWM
2V
–
+
MAIN SWITCH
DRIVER
A7
A8
100μA
+
–
V
IN
SW
Q1
POWER
SWITCH
LT3517
V
GND
REF
3517 F01
7
3517f