Shouding
1A/30V LED Driver
General Description
The SD3362 is a step-down DC/DC converter
designed to drive LEDs with a constant current. The
device can drive up to 8 LEDs, depending on the forward
voltage of the LEDs, in series from a voltage source of 6V
to 30V. Series connection of the LEDs provides identical
LED currents resulting in uniform brightness and
eliminating the need for ballast resistors. The SD3362
switches at frequency up to 1MHz. This allows the use
of small size external components, hence minimizing the
PCB area needed.
Maximum output current of SD3362 is set via an
external resistor connected between the VIN and SET
input pins. Dimming is achieved by applying either a DC
voltage or a PWM signal at the CTRL input pin. An input
voltage of 0.4V or lower at CTRL switches off the output
MOSFET simplifying PWM dimming.
SD3362
Features
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LED driving current up to 1A
Better than 5% accuracy
High efficiency up to 98%
Operating input voltage from 6V to 30V
High switching frequency up to 1MHz
PWM/DC input for dimming control
Built-in output open-circuit protection
Applications
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MR 16 lamps
General illumination lamps
Pin Configuration
SOT23-5L
Pin
Name
Pin No.
SW
1
GND
2
Switch Pin. Connect inductor/freewheeling diode here, minimizing track
length at this pin to reduce EMI.
GND Pin
CTRL
3
Dimming and On/Off Control Input.
SET
4
Vin
5
www.shouding.net
Pin Function
Set Nominal Output Current Pin. Configure the output current of the
device.
Input Supply Pin.
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Shouding
1A/30V LED Driver
SD3362
Typical Application Circuit
SD3362
Absolute Maximum Ratings
Parameter
Continuous pin voltage relative to GND
SW voltage relative to GND
CTRL pin input voltage
Symbol
VIN
VSW
VCRTL
Rating
-0.3~36
-0.3~36
-0.3~6
Unit
V
V
V
DC or RMS Switch current
ISW-DC
1.25
A
Peak Switch current (
