SGM3141B Datasheet, PDF (1/14 Pages) SG Micro Corp – Charge Pump LED Driver

SGM3141B
700mA Buck/Boost
Charge Pump LED Driver
GENERAL DESCRIPTION
The SGM3141B is a current-regulated charge pump
ideal for powering high brightness LEDs for camera
flash applications. The charge pump can be set to
regulate two current levels for Flash and Torch modes.
The SGM3141B automatically switches modes
between step-up and step-down ensuring that LED
current does not depend on the forward voltage. It
switches at 2.2MHz, allowing the use of tiny
components. The supply voltage ranges from 2.7V to
5.5V and is ideally suited for all applications powered
by a single Li-ion battery cell or three to four NiCd,
NiMH, or Alkaline battery cells.
FEATURES
● Output Current Up to 700mA
● Up to 90% Efficiency in Torch Mode
● Adjustable Flash Mode Current
● 1× and 2× Automatic Modes for High Efficiency
● Input Voltage Range: 2.7V to 5.5V
● Minimum External Components: No Inductors
● High Frequency Operation: 2.2MHz
● Low 47mV Reference for Low Loss Sensing
● I_Q < 1μA in Shutdown
● Built-In Soft-Start Limits Inrush Current
● Low Input and Output Ripple and Low EMI
● Output Over-Voltage Protection
● Over-Current and Over-Temperature Protection
● Available in Green TDFN-3×3-10L Package
The SGM3141B also features a very low shutdown
current, an automatic soft-start mode to limit inrush
current, as well as over-current, over-voltage and
over-temperature thermal shutdown control.
A low current-sense reference voltage (47mV) allows
the use of small 0603 current sensing resistors.
The SGM3141B is available in Green TDFN-3×3-10L
package and is specified over an ambient temperature
range of -40℃ to +85℃.
APPLICATIONS
White LED Torch, Flash for Cell
Phones, DSCs and Camcorders
White LED Backlighting
Generic Lighting, Flash and Strobe Applications
General Purpose High Current Boost
TYPICAL APPLICATION
VIN
2.7V to 5.5V
CIN
4.7μF
CF
1μF
TORCH/FLASH
ENABLE
1 _VIN
VOUT ¹⁰
2 _C1
9
PGND
COUT
1μF
SGM3141B
3
C2
8
SGND
4
FLASH
7
FB
5 _EN
6
RSET
RSET
86.6kΩ
WLED
RSENSE
0.22Ω
SG Micro Corp
www.sg-micro.com
REV. A