LT3496 LINER [Linear Technology], LT3496 Datasheet - Page 7

• Manufacturer Part Number: LT3496
• Description: Triple Output LED Driver
• Manufacturer: LINER [Linear Technology]

PIN FUNCTIONS
PWM1, PWM2, PWM3: Pulse Width Modulated Input.
Signal low turns off the respective converter, reduces
quiescent supply current and causes the VC pin for that
converter to become high impedance. PWM pin must not
be left fl oating; tie to V
V
nominal Output Voltage is 2V.
CTRL1, CTRL2, CTRL3: LED Current Adjustment Pins. Sets
voltage across external sense resistor between CAP and
LED pins of the respective converter. Setting CTRL voltage
to be less than 1V will control the current sense voltage to
be one-tenth of CTRL voltage. If CTRL voltage is higher than
1V, the default current sense voltage is 100mV. The CTRL
pin must not be left fl oating.
FADJ: Switching Frequency Adjustment Pin. Setting FADJ
voltage to be less than 1V will adjust switching frequency
up to 2.1MHz. If FADJ voltage is higher than 1V, the default
switching frequency is 2.1MHz. The FADJ pin must not
be left fl oating.
VC1, VC2, VC3: Error Amplifi er Compensation Pins. Con-
nect a series RC from these pins to GND.
OVP1, OVP2, OVP3: Open LED Protection Pins. A voltage
higher than 1V on OVP turns off the internal main switch
of the respective converter. Tie to ground if not used.
TG1, TG2, TG3: The Gate Driver Output Pin for Disconnnect
P-Channel MOSFET. One for each converter. When the
REF
: Reference Output Pin. Can supply up to 200μA. The
REF
if not used.
PWM pin is low, the TG pin pulls up to CAP to turn off
the external MOSFET. When the PWM pin is high, the ex-
ternal MOSFET turns on. CAPn-TGn is limited to 6.5V to
protect the MOSFET. Leave open if the external MOSFET
is not used.
LED1, LED2, LED3: Noninverting Input of Current Sense
Error Amplifi er. Connect directly to LED current sense
resistor terminal for current sensing of the respective
converter
CAP1, CAP2, CAP3: Inverting Input of Current Sense Error
Amplifi er. Connect directly to other terminal of LED current
sense resistor terminal of the respective converter.
SW1, SW2, SW3: Switch Pins. Collector of the internal
NPN power switch of the respective converter. Connect
to external inductor and anode of external Schottky recti-
fi er of the respective converter. Minimize the metal trace
area connected to this pin to minimize electromagnetic
interference.
V
the internal control circuitry.
SHDN: Shutdown Pin. Used to shut down the switching
regulator and the internal bias circuits for all three convert-
ers. Tie to 1.5V or greater to enable the device. Tie below
0.4V to turn off the device.
Exposed Pad: Signal Ground and Power Ground. Solder
paddle directly to ground plane.
IN
: Input Supply Pin. Must be locally bypassed. Powers
LT3496
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