Wide Input and Output Range: This DC-DC buck-boost module supports a wide input voltage range of 4.5-21V, making it suitable for various power supply and battery applications. Buck-Boost Conversion Function: Designed with a high-efficiency buck-boost topology, this module can both step down and step up the voltage to ensure a stable output, even when the input voltage is higher, lower, or equal to the desired output voltage. 3A Constant Current Limiting: Built-in 3A current limiting capability provides constant current output, effectively protecting batteries and loads. It is ideal for LED driving, battery charging, and other applications requiring stable current control. Lithium Battery Voltage Stabilization: Optimized for lithium battery use, this module helps stabilize the battery voltage during charging and discharging, improving safety and extending the service life of single or multiple lithium cells. Application: Stable DC output for various devices, works when input is above or below output voltage. Name: DC Buck-Boost Module Type: Non-isolated Buck-Boost Working Mode: PFM Input Voltage: 4.5-21V (recommended 5-20V) Voltage Accuracy: ±0.05V (actual output may be 0.1-0.2V higher, adjustable) Input Current: <10A (peak) Output Current Limit: 0-3A (user-definable, max 3A) Output Voltage: 5V Line Compensation: 50mV/A Protections: Under-voltage, input/output current limit, over-temperature, short circuit Control Interface: UART (TX, RX, GND) Output Control: External low-level trigger / UART command Switching Frequency: 460kHz Output Ripple: <30mV Standby Current: <5mA Operating Temperature: -40°C to +85°C Cooling: Natural air Color: Green Material: PCB Package Contents: 1 * DC-DC Buck-boost Module Only the above package content, other products are not included. Note: Light reflection 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.