SGM3146 Datasheet, PDF (1/12 Pages) SG Micro Corp – Driver with Low Dropout Current Source

SGM3146
8-Channel Charge Pump White LED
Driver with Low Dropout Current Source
GENERAL DESCRIPTION
The SGM3146 is a high performance white LED driver.
It integrates current sources and automatic mode
selection charge pump. The part maintains the high
efficiency by utilizing a 1×/1.5× fractional charge pump
and low dropout current sources. The small equivalent
1× mode open loop resistance and ultra-low dropout
voltage of current source extend the operating time of
1× mode and optimize the efficiency of Li-ion battery in
white LED applications.
The SGM3146 supports up to 8 white LEDs and
regulates a constant current which the initial value can
be set by an internal resistor. The part implements a
4-bit DAC for brightness control. Users can easily
configure the LED current from 1.65mA to 27mA by a
serial pulse. The dimming of white LEDs current can be
achieved by applying a pulse signal to the EN/SET pin.
There are totally 16 steps of current could be set by
users. The operating voltage range is 2.7V to 5.5V.
Internal soft-start circuitry effectively reduces the
in-rush current while both start-up and mode transition.
The SGM3146 is available in Green TQFN-3×3-20L
package and is rated over the -40℃ to +85℃
temperature range.
FEATURES
 Input Voltage Range: 2.7V to 5.5V
 Drives up to 8 LEDs at 27mA Each
 One Single Wire Interface
 16-Step Brightness Control
 High Efficiency by Fractional Conversion with
1× and 1.5× Modes
 Switching Frequency: 0.93MHz
 Regulated Output Current with ±4.8% Matching
 Internal Soft-Start Limits Inrush Current
 Low Input Ripple and Low EMI
 Over-Current and Over-Temperature Protection
 Under-Voltage Lockout with Hysteresis
 Available in Green TQFN-3×3-20L Package
APPLICATIONS
Mobile Phone, DSC, MP3
White LED Backlighting
LCD Display Supply
SG Micro Corp
www.sg-micro.com
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