this design requires 20mA

 this design requires 20mA 16V maximum output current and voltage. The specifications of the   MR16 mobile phone screen brightness adjustment function with mobile phones in general idle time can gradually reduce the screen brightness. System processor is responsible for providing the required PWM dimming function digital signal. Battery life is a major consideration,

 so efficiency should be improved. Mobile phone screen about 98% of the time in standby mode, thus requiring white LED driver power supply with load disconnect function, in order to prolong battery life. Limited by the volume of the mobile phone, to a small integrated solution using TPS61043 to meet these requirements. It is the inductive boost converter, built-in power FET   T8 Tube tube, it is also designed specifically for white LED driver. TPS61043 also provides load disconnect, overvoltage protection and PWM dimming function, which can be used to 1MHz switching frequency smallest external components.

(1) Sense Resistor Selection

LED Flexi

    Using TPS61043 white LED driver power supply constitutes an external circuit is designed primarily how to properly select the external components, while completing the appropriate circuit layout. Current sense resistor value is determined by the reference voltage of 0.252V TPS61043 dividing the required maximum current of 0.02A white LED determined that the current sense resistor value 12.6Ω, resistor power dissipation is 5mW, so choose 0402-type resistor device to save board space.