SGM3784.pdf
No.10924
● Ultra Compact Solution
Small, WLCSP-2×1.6-12B Package
Smallest Footprint, 1mm-Height, 1μH Power Inductor
● LED Current Source for Local LED Grounding
Simplified Routing to and from LEDs
Improved LED Thermal Dissipation
● Synchronous 3MHz PWM Boost Converter, No External Diode
● High Efficiency: 95% Peak
● I2C Programmable
Currents up to 1.1A in Flash Mode per LED
When VIN is not Lower than 3.6V (The Total 2 LEDs
Current is 1.5A When VIN is Lower than 3.6V)
Torch Mode
Programmable DC Battery Current Limit
Programmable Flash Timer up to 1600ms
Low Battery Mode to Reduce LED Current Automatically
● Device Control
I2C-Compatible Control Registers
External STROBE and Torch Input Pins
Transmitter Mask (TxMASK) Input
● Safety Features
Thermal Overload Protection
Inductor Fault Detection
LED Short-Circuit/Open-Circuit Protection
The SGM3784 is a very compact, highly efficient, dual white LED flash driver for high resolution camera phones that improves picture and video quality in low light environments. The device integrates a programmable 1.6MHz or 3MHz synchronous inductive boost converter, an I2C-compatible interface, and two 1.1A current sources. The high switching frequency enables the use of a tiny, 1mm high, low cost, 1μH power inductor, and the parallel current sources permit LED cathode grounding for thermally enhanced, low EMI and compact layouts.
The LED driver maximizes efficiency over the entire battery voltage range to maximize the input-power-to- LED-power conversion and minimize battery current draw during flash events. A programmable DC battery current limit safely maximizes LED current for all LED forward voltage and battery voltage conditions. A Transmitter Mask (TxMASK) input enables fast reduction of the flash LED currents and battery current during a power amplifier current burst. The
I2C-compatible interface can be used to program timers and currents and to read back status bits for operation monitoring and safety control.
