IS31LT3360-SDLS3-TR

IS31LT3360 40V/1.2A LED DRIVER WITH INTERNAL SWITCH January 2014 GENERAL DESCRIPTION FEATURES 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 less than 0.2V 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. It operates from 6V to 40V over two temperature ranges of -40°C to +105°C and -40°C to +125°C.       Up to 1.2A output current High efficiency (up to 98%) Wide input voltage range: 6V ~ 40V Internal 40V power switch Simple low parts count Typical 3% output current accuracy (-40°C to +105°C, IS31LT3360-SDLS3-TR) Typical 5% output current accuracy (-40°C to +125°C, IS31LT3360-SDLS4-TR) Single pin on/off and brightness control using DC voltage or PWM Up to 1MHz switching frequency Inherent LED open-circuit/short-circuit protection Thermal shutdown protection circuitry Up to 1200: 1 dimming ratio APPLICATIONS        Automotive and avionic lighting LED MR16, MR11 spot light LED street light PAR light Industrial lighting Refrigeration lights Other LED lighting TYPICAL APPLICATION CIRCUIT Figure 1 Typical Application Circuit Note: The capacitor, C2, can’t be removed. And it should be placed as close as possible to the VIN and GND pins, otherwise the operation might be abnormal. Lumissil Microsystems – www.lumissil.com Rev. C, 12/22/2013 1 IS31LT3360 PIN CONFIGURATION Package SOT89-5 Pin Configuration LX 1 GND 2 ADJ 3 5 VIN Thermal Pad 4 ISENSE PIN DESCRIPTION No. Pin Description 1 LX Drain of power switch. 2 GND Ground (0V). 3 ADJ Multi-function On/Off and brightness control pin: * Leave floating for normal operation.(VADJ = VREF = 1.2V giving nominal average output current IOUT(NOM) =0.1/RS ) * Drive to voltage below 0.2V to turn off output current * Drive with DC voltage (0.3V