ISSI IS31LT3360 Manual

IS31LT3360 3CH DEMO BOARD GUIDE
DESCRIPTION
The IS31LT3360 is a continuous mode inductive
step-down converter, designed for driving a single LED
or multiple series connected LEDs efficiently from a
voltage source higher than the LED voltage. The chip
operates from an input supply between 6V and 40V
and provides an externally adjustable output current of
up to 1.2A.
The IS31LT3360 includes an integrated output switch
and a high-side output current sensing circuit, which
uses an external resistor to set the nominal average
output current.
Output current can be adjusted linearly by applying an
external control signal to the ADJ pin. The ADJ pin will
accept either a DC voltage or a PWM waveform. This
will provide either a continuous or a gated output
current.
Applying a voltage of 0.2V or lower to the ADJ pin
turns the output off and switches the chip into a low
current standby state.
The chip is assembled in SOT89-5 package.
IS31LT3360 3CH DEMO board is used in RGB lamp or
the general LED lamp.
FEATURES

Simple low parts count

Internal 40V power switch

Wide input voltage range: 6V to 40V

Up to 1.2A output current

High efficiency (up to 98% )

Typical 1200:1 dimming rate

Typical 3% output current accuracy

Single pin on/off and brightness control using DC
voltage or PWM

Up to 1MHz switching frequency

Inherent open-circuit LED protection

Thermal shutdown protection circuitry
QUICK START
Figure 1: Photo of IS31LT3360-3CH Evaluation Board
Integrated Silicon Solution, Inc. – www.issi.com
Rev. B, 04/27/2016
RECOMMENDED EQUIPMENT

40VDC power supply

3 pcs of LED panel (3 WLEDs, 10 LEDs in series
on each panel)

Multi-meter
RECOMMENDED INPUT AND OUTPUT RATINGS

Input: 6~40VDC

Output: 1~10 LEDs in series/667mA
Note: The input voltage must be 2V higher than the output
voltage (total V ).
F
ABSOLUTE MAXIMUM RATINGS

Input voltage ≤ 40VDC
Caution: Do not exceed the conditions listed above, otherwise
the board will be damaged.
PROCEDURE
The IS31LT3360 DEMO Board is fully assembled and
tested. Follow the steps listed below to verify board
operation.
Caution: Do not turn on the power supply until all connections
are completed.
1) Connect the terminals of the power supply to the
AC1 and AC2 pin(If the board don't have the
rectifier(D1-D4), Connect the positive terminal of
the power supply to the VCC of the board and the
negative terminal of power supply to the GND of
the board) .
2) Connect the negative of the one of LED panel
(LED arrays) to the LED1- terminal. And connect
the positive of the same LED panel (LED arrays)
to the LED1+ terminal.
3) Connect the other two LED panels to LED2 and
LED3 as above.
4) Turn on the power supply and the LED panels
(LED arrays) will be light.
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