4A Buck Boost Converter Module Adjustable Step Down with LCD Display Power (HW-140)

4A Buck-boost power supply module includes two main control buttons – IN/OUT and ON/OFF:

• IN/OUT Button: Switches between input and output voltage display. Long press to view output current and power.
• ON/OFF Button: Controls the output state. Long press to set the default power-on status (ON or OFF).

CC (Constant Current) and CV (Constant Voltage)

The CC potentiometer adjusts the output current. Turn clockwise to increase current. When load current reaches the set limit, the module enters constant current mode, and the red CC indicator lights up.
The CV potentiometer adjusts the output voltage. Turn clockwise to increase voltage. The ON indicator shows when output voltage is active.

How to Use?

• Step 1: Use as a standard buck-boost module with overcurrent protection.
• Step 2: Adjust the CV (voltage) to your desired output voltage.
• Step 3: Use a multimeter (10A range) to measure short-circuit current. Adjust CC to set the desired overcurrent protection limit.
• Note: A small voltage drop (0–0.2V) may occur due to the output resistor and wire resistance during high current usage. This is normal.

Key Features

• 4A Buck-Boost Converter with LCD voltage/current display
• Adjustable Step-Up and Step-Down power control
• Built-in constant voltage and current protection
• ON/OFF switch memory function
• Ideal for DIY electronics, battery charging, and power supply projects