LT3466 Linear Technology, LT3466 Datasheet - Page 6

• Manufacturer Part Number: LT3466
• Description: Dual Full Function White LED Step-Up Converter with Built-In Schottky Diodes
• Manufacturer: Linear Technology

PI FU CTIO S
LT3466
V
to the cathode of the internal Schottky diode. Connect an
output capacitor from this pin to ground.
SW1 (Pin 2): Switch Pin for Converter 1. Connect the
inductor at this pin.
V
with a 1 F, X5R or X7R type ceramic capacitor.
SW2 (Pin 4): Switch Pin for Converter 2. Connect the
inductor at this pin.
V
to the cathode of the internal Schottky diode. Connect an
output capacitor from this pin to ground.
FB2 (Pin 6): Feedback Pin for Converter 2. The nominal
voltage at this pin is 200mV. Connect cathode of the lowest
LED and the feedback resisitor at this pin. The LED current
can be programmed by :
6
OUT1
IN
OUT2
I
I
U
LED2
LED2
(Pin 3): Input Supply Pin. Must be locally bypassed
(Pin 1): Output of Converter 1. This pin is connected
(Pin 5): Output of Converter 2. This pin is connected
U
(200mV/R
(V
CTRL2
/5 • R
U
FB2
), when V
FB2
), when V
CTRL2
CTRL2
> 1.6V
< 1V
CTRL2 (Pin 7): Dimming and Shutdown Pin for Con-
verter 2. Connect this pin to ground to disable the con-
verter. As the pin voltage is ramped from 0V to 1.6V, the
LED current ramps from 0 to I
voltage above 1.6V does not affect the LED current.
R
Frequency. The switching frequency can be programmed
from 200KHz to 2MHz.
CTRL1 (Pin 9): Dimming and Shutdown Pin for Con-
verter 1. Connect this pin to ground to disable the con-
verter. As the pin voltage is ramped from 0V to 1.6V, the
LED current ramps from 0 to I
voltage above 1.6V does not affect the LED current.
FB1 (Pin 10): Feedback Pin for Converter 1. The nominal
voltage at this pin is 200mV. Connect cathode of the lowest
LED and the feedback resistor at this pin. The LED current
can be programmed by :
Exposed Pad (Pin 11): The Exposed Pad must be soldered
to the PCB system ground.
T
I
I
LED1
LED1
(Pin 8): Timing Resistor to Program the Switching
(200mV/R
(V
CTRL1
/5 • R
FB1
), when V
FB1
), when V
LED2
LED1
CTRL1
(= 200mV/R
(= 200mV/R
CTRL1
> 1.6V
< 1V
FB2
FB1
). Any
). Any
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