Adjustable buck-boost module: voltage range is DC 5.5-30V; Output voltage range is DC 0.5-30V, can be arbitrary adjustable; The output current range is 0-3A, can be arbitrary adjustable, if enhance heat dissipation, it can reach 4A; The output power can up to 35W, if enhance dissipation, it can reach 50W. With protection function: the volt former board is with reverse connection protection at input terminal, reverse connection not burn; Stop the current from feeding back protection at output terminal; Short circuit protection; Backflow prevention at the output, when charging the battery, there is no need to add a second anti-backflow tube. Bright LCD display: the voltage regulator module is designed with LCD, can display input and output voltage, output current and output power; Voltage display resolution is 0.05V, current display resolution is 0.005A; Low output ripple, with LC filter Button control: the IN/ OUT button switches the display of input voltage and output voltage; Long can switch the display of output current and output power; the ON/OFF button controls the output ON or OFF; Long can set the default output state of power-on to ON or OFF. Application: the switching power supply can be applied as an ordinary buck-boost module with over-current protection; as a battery charger or a high-power LED constant current driver module Features: 1. The module has IN/OUT and ON/OFF buttons: IN/OUT button switches the display of input voltage and output voltage, long can switch output current and output power display; ON/OFF button controls output ON or OFF, long can Set the default output state of power-on to ON or OFF. 2. CC is the current setting potentiometer. Turn clockwise to increase the setting current. When the load current is set to the current, it enters the constant current state,and the CC constant current indicator (red) lights up; the right CV is the voltage setting potential The output voltage can be increased by rotating clockwise. The ON indicator light is an output status indicator light. It lights up when there is voltage on the output terminal, otherwise it goes off. color: blue Material: PCB, Metal Specifications: Input voltage: 5.5-30V Output voltage: 0.5-30V Output current: 3A (work stably), 4A (under enhanced heat dissipation) Output power: 35W (natural heat dissipation), 50W (enhanced heat dissipation) Voltage display resolution: 0.05V Current display resolution: 0.00 Conversion efficiency: about 88% Input reverse connection protection: Yes Backflow prevention at the output: Yes Short circuit protection: Yes Working frequency: 180KHZ Size: 66 x 48 x 21mm / 2.6 x 1.9 x 0.8in Mounting hole: diameter 4mm Precautions: 1. Module input IN- must not be short-circuited with output OUT-, otherwise the constant current function fail. 2. Please make sure that the power of the power supply is always the power required by the output load! 3. If the module wants to output at full load, the input voltage must be above 8V. When the input voltage is 5V, the output power is about 15W, and the volt-ampere meter fails. The module current value is as large as 4A, provided that it is limited by the large output pow Package Contents: 1 x Adjustable buck-boost module Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.