DC-DC Converter Step Up Boost Module 600MA 0.9V-5V to 5V USB Power Supply Module Feature: Module Properties: non-isolated step-up module (BOOST) input voltage: 1-5V Output voltage: 5.1-5 .2 V Output Current: Rated 1A-1.5A (single lithium input), the maximum 1.5A (single lithium input) Efficiency: Up to 96% (the higher the input voltage, the higher the efficiency) Switching frequency: 500KHz Output ripple: 30mV (MAX) 20M bandwidth (input 4V output 5.1V 1A) Voltage indication: LED lights with load (input voltage less than 2.7V LED indicator off) Operating Temperature: Industrial (-40°c to +85°c) Full load temperature rise: 30°c Quiescent Current: 130uA Load regulation: ± 1% Voltage regulation: ± 0.5% Dynamic response speed: 5% 200uS Short circuit protection: None (Please use the lithium battery with protection.) Input Reverse Polarity Protection: None Connection: Welding Input: IN + Postive, IN-Negative Output: USB Output Applications:  DIY a mobile power supply, only need one battery, you can output 5V voltage for your phone, MP3, MP4, PSP charger, very easy. In order to power your electronic devices when your device needs 5V power supply, when you only have lithium battery, this module can be directly step-up to 5V, solve your problems.