GENERAL DEscriptION

The SGM3749 is a high efficiency white LED driver with a 1.25MHz boost converter. With the fixed switching frequency and an internal 40V/1.5A switch FET, the SGM3749 is designed for powering high brightness LEDs in general lighting.

The SGM3749 is capable of driving up to 10 white LEDs in series. The FB feedback voltage is regulated at 200mV typically. The default LED current is programmed by an external RSET resistor. During the operation, the LED current can be controlled by applying a PWM signal to the CTRL pin. The feedback voltage depends on the PWM signal duty cycle. For PWM dimming control, there are no audible noises on the output capacitor.

The SGM3749 integrates LED open protection. It prevents the device from damaging due to the over- voltage during LED open conditions.

The SGM3749 is available in Green TDFN-2×2-6L and TSOT-23-6 packages. It operates over an ambient temperature range of -40℃ to +85℃.

FEATURES

• Input Voltage Range: 3V to 20V

• Integrated 40V/1.5A Switch

• Up to 90% Efficiency

• Switching Frequency: 1.25MHz

• Feedback Voltage: 200mV

• PWM Dimming Control

• PWM Dimming Frequency: 5kHz to 100kHz

• 38V LED Open Protection for 10 LEDs

• 600kΩ Pull-Down Resistor on CTRL Pin

• Dimming Stable in More than 1:500 PWM Range

• Automatic Soft-Start for Reducing Inrush Current

• -40℃ to +85℃ Operating Temperature Range

• Available in Green TDFN-2×2-6L and TSOT-23-6 Packages

APPLICATIONS

Backlight for Media Form Factor Display

High Brightness LED Lighting