GENERAL DEscriptION
The SGM3785S is a highly integrated Boost DC/DC converter with 2MHz fixed fre High switching frequency makes it easy to use small components and optimized for portable photoflash. The SGM3785S is ideal for high power flash LEDs which are suitable for mobile phone camera modules and digital still cameras.
The SGM3785S offers excellent flexibility to enter flash mode and movie/torch mode through the ENF and ENM pins respectively. Flash mode is usually used with 670ms timer control to generate a high intensity flash. The maximal flash current and movie/torch current are respectively programmed through external resistors (RSETF and RSETM), which can provide simple control for the flash LED solution. The real LED current in flash mode and movie/torch mode can be programmed by external PWM signal on ENM pin.
The D1 and D2 pins can be tied together to drive higher power single flash LEDs, sinking up to 1.5A continuous current. The integrated thermal regulation in flash mode limits the temperature of the device to prevent the device from triggering thermal shutdown by reducing the LED sink current below the programmed value.
The SGM3785S provides very low shutdown current. It also includes a comprehensive set of protection features such as over-voltage protection, LED open or short protection and thermal shutdown.
The SGM3785S is available in a Green TDFN-3×2-14L package. It operates over an ambient temperature range of -40℃ to +85℃.
FEATURES
Input Voltage Range: 3V to 5V
Up to Total 1.5A LED Current
Up to 90% Efficiency
Dual Flash LED Outputs
Tiny Inductor: 1.0μH
2MHz Boost Converter
Separate Flash Mode Enable and Movie/Torch
Mode Enable Control Pins
Flash Current and Movie/Torch Current can be Programmed through PWM Signal on ENM Pin
Independent Resistors Set Flash Current and Movie/Torch Current Respectively
Integrated Thermal Regulation Control
670ms Flash Timer Control
360kΩ Pull-Down Resistor on ENM and ENF Pins
Protection Features
Output Over-Voltage Protection
LED Open or Short Protection
Cycle-by-Cycle Current Limit
Less than 1μA Shutdown Current
Available in a Green TDFN-3×2-14L Package
Temperature Range: -40℃ to +85℃
APPLICATIONS
Portable E