Features: 100 percent brand new and high quality. This is a DC-DC boost converter module with working frequency of 1 MHz.The module has high efficiency up to 94 percent , usually can be 84 percent -91 percent . Ultra small size and light weight, it is convenient to use. Widelyused for battery-powered devices, multimeter, small power motors, cameras, electric toys, model aircraft, LED lighting, electronic DIY kits, etc. Specification:Output voltage: 3.7V, 5V, 12V (Optional) Efficiency: 94 percent (usually is 84 percent -91 percent )Quiescent current: 0.19mAOperating temperature range : -40-and85 Degrees CelsiusStorage temperature range : -65-and150 Degrees Celsius Size: 13x11x5.2mm or 0.5x0.4x0.2in Weight: 2g or 0.1oz (approx.) Protection : Over current protection(OCP)Over voltage protection(OVP)Short circuit protection(SCP)Over temperature protection(OTP) Pin description:Vi : Input positive(and)GND : Input and Output negative(GND or -)Vo : Output positive(and)Output 3.7V :Input voltage: DC 2.6 - 3.6Voutput voltage: DC 3.7V3 percent Maximum output : 3.7V or 1200MA(See the table below for details)Output 5V :Input voltage: DC 2.6 - 4.5VOutput voltage: DC 5V3 percent Maximum output : 5V or 1200MAOutput 12V :Input voltage: DC 2.6 - 6VOutput voltage: DC 12V3 percent Maximum output : 12V or 500MA Package list:1 x Module Note:This is a DC - DC voltage converter module, please pay attention when using:1, The input voltage should not be higher than maximum input range.2, The output power cannot be higher than the maximum load for a long time.3, The input power must be higher than output power, because of the power consumption of the module itself.FAQ:Q: Why the output voltage is lower than the nominal voltage A :Because the input power is too low.Use a multimeter to test the input voltage, the input voltage is very low at this time. .