DESCRIPTION：

The LT®3935 is a monolithic, synchronous, step-downDC/DC converter that utilizes fixed-frequency, peak currentcontrol and provides PWM dimming for a string of LEDs.The LED current is programmed by an analog voltage orthe duty cycle of pulses at the CTRL pin. An output voltage limit can be set with a resistor divider to the FB pin.The switching frequency is programmable from 200kHz to2MHz by an external resistor at the RT pin or by an externalclock at the SYNC/SPRD pin. With the optional spreadspectrum frequency modulation enabled, the frequencyvaries from 100% to 125% to reduce EMI.Additional features include an LED current monitor, anaccurate EN/UVLO pin threshold, open-drain fault reporting for open-circuit and short-circuit load conditions,and thermal shutdown. The LT3935 utilizes proprietarySilent Switcher technology for very low EMI.

FEATURES：

±1.5% LED Current Regulationn 

±1.2% Output Voltage Regulationn

Spread-Spectrum Frequency Modulationn 

Silent Switcher® Architecture for Low EMIn 

3.6V to 36V Input Voltage Rangen 

0V to 36V LED String Voltagen 

200kHz to 2MHz with SYNC Functionn 20:1 Analog or Duty Cycle LED Current Controln 

Open/Short LED Fault Indicationn 

Accurate LED Current Sense with Monitor Outputn 

Programmable UVLOn 

Thermally Enhanced 28-Lead (5mm × 4mm) LQFN

APPLICATIONS：

Automotive Lightingn 

Industrial and General Purpose Lighting