
LT3003
PIN FUNCTIONS
V EE (Pin 10): Lower Rail.
? Boost: Connect to System Ground
? Buck Mode: Connect to Inductor
? Buck-Boost Mode: Connect to Input Supply
BLOCK DIAGRAM
Exposed Pad (Pin 11): GND. The ground for the IC should
be soldered to a continuous copper ground plane under
the LT3003 die. Soldering the Exposed Pad to the copper
ground plane under the device will reduce thermal resis-
tance and increase the power capability of the LT3003.
1
LED1
4
V MAX
2
LED2
3
LED3
V IN
B1
+
B2
+
B3
–
–
B1 B2 B3
V EE
10
PWM
+
V IN
5
LOGIC
V EE
–
3V
6
PWM
+
+
SHDN
9
0.5V
–
–
0.7V
OT1
7
BIAS
THERMAL
SHUTDOWN
BG
BG
125 ° C
OT2
8
150 ° C
11
EXPOSED PAD
3003 F01
Figure 1. Block Diagram
3003fa
5